Category: Important Questions

Students get through the TN Board 12th Bio Zoology Important Questions Chapter 3 Reproductive Health which is useful for their exam preparation.

TN State Board 12th Bio Zoology Important Questions Chapter 3 Reproductive Health

Very short answer questions

Question 1.
What is amniocentesis?
Answer:
Amniocentesis is a technique used to find out any chromosomal abnormalities in the foetus.

Question 2.
Expand the abbreviation POCSO and PCPNDT.
Answer:

1. POCSO – Prevention of Children from Sexual Offences.
2. PCPNDT – Preconception and Prenatal Diagnostic Technique.

Question 3.
Define Birth control.
Answer:
Birth control is the voluntary use of contraceptive methods to prevent childbirth, by preventing fertilization of egg or by preventing the implantation of the embryo in the uterus.

Question 4.
What is the natural contraceptive method?
Answer:
The natural contraceptive method is the procedure to prevent the meeting of sperm with ovum in order to prevent fertilization.

Question 5.
Mention any two chemical barriers used in the contraceptive methods.
Answer:

1. Foaming tablets
2. Melting suppositories

Question 6.
Explain briefly the hormonal barrier in the contraceptive devices.
Answer:
The hormonal barrier is a contraceptive method, in which the hormonal imbalance prevents the ovaries from releasing ova and thickens the cervical fluid. This keeps the sperm away from the ovum.

Question 7.
What are Non-medicated IUDS?
Answer:
Non-medicated IUDs are intrauterine devices made of plastic or stainless steel.
Eg: the Lippes loop is a double S-Shaped plastic device.

Question 8.
Name any two copper releasing lUDs.
Answer:

1. NOVaT
2. Multiload 375.

Question 9.
Name any two bacterial sexually transmitted diseases.
Answer:

1. Chlamydiosis
2. Syphilis

Question 10.
What are the risk factors for cervical cancer? The risk factors for cervical cancer include:
Answer:

1. Having sex with multiple unknown partners.
2. Prolonged use of contraceptive pills.

Question 11.
Define Assisted Reproductive Technology (ART).
Assisted reproductive technology is a collection of procedures, in which the handling of gametes and/or embryos outside the body to achieve a pregnancy are carried out.

Question 12.
Define Mayer-Rokintansky syndrome.
Answer:
Mayer-Rokintansky syndrome is a condition, in which women do not have a functional uterus.

Question 13.
What is the embryo transfer technique?
Answer:
The embryo transfer technique is the method of transferring an embryo with cells more than the blastomere stage into the uterus.

Question 14.
Define Azoospermia.
Answer:
Azoospermia is defined as the absence of spermatozoa in the ejaculated semen on at least two occasions.

Question 15.
What is Foetoscope?
Answer:
Foetoscope is an instrument used to monitor the heart rate of foetus and other functions during late pregnancy and labor.

Short answer questions

Question 1.
List the health care programs taken up by the Government of India.
Answer:

1. Massive child immunization.
2. Supply of nutritional food to pregnant women.
3. Implementation of Janani Suraksha Yojana, Janani Shishu Suraksha Karyakram, RMNCH + A approach (An integrated approach for reproductive, maternal, newborn, child, and adolescent health), Pradhan Mantri Surakshit Matriva Abhiyan, etc…

Question 2.
The sex ratio in India has changed from 919 females to every 1000 males. How? Explain.
Answer:
The female foeticide and female infanticide is a manifestation of gender discrimination, in our society, which increases the female foeticide and female infanticide. This leads to the imbalance of sex ratio in our society and to correct this ratio to normal, steps are needed to change the mindset and attitude of people, especially in young adults.

Question 3.
Define lactational amenorrhoea. Explain it as a natural birth control method.
Answer:
Lactational amenorrhoea is defined as the delay in the ovarian cycle due to breastfeeding after childbirth. It serves as a natural, but unreliable form of birth control. During breastfeeding, the sucking of milk by the baby stimulates the pituitary to secrete more prolactin in order to increase milk production. The increased level of prolactin in the blood of the mother may prevent the menstrual cycle by suppressing the release of GnRH (Gonadotropin-Releasing Hormone) which in turn suppresses the production of gonadotropin from the pituitary. Thus lactational amenorrhoea indirectly acts as a natural birth control agent.

Question 4.
Write briefly about oral contraceptives.
Answer:
Oral contraceptives are taken orally in the form of pills, used to prevent ovulation in females. They inhibit the secretion of FSH and LH hormones. The most commonly used birth control pills are combined pills, which contain synthetic progesterone and estrogen hormones. Central Drug Research Institute (CDRI) in Lucknow, India developed a nonsteroidal contraceptive pill, called saheli.

Question 5.
Mention the fungal sexually transmitted disease, their causative organisms, and symptoms.
Answer:
Candidiasis: The causative organism is Candida albicans.
Symptoms: It attacks the mouth, throat, intestinal tract, and vagina. It also causes vaginal itching or soreness, abnormal vaginal discharge, and pain during urination.
Trichomoniasis: This disease is due to the fungal infection by Trichomonas vaginalis.
Symptoms: It causes vaginitis, greenish-yellow vaginal discharge, itching, and burning sensation, urethritis, epididymitis, and prostatitis.

Question 6.
What are the causes of infertility in men?
Answer:

1. Undescended testes and swollen veins (Varicocoele) in the scrotum,
2. The rise of temperature in the scrotum due to tight clothing in men may affect sperm production.
3. Underdeveloped testes.
4. Males may develop an autoimmune response to their own sperm.

Question 7.
Name any three procedures followed under assisted reproductive technology.
Answer:
The ART includes:

1. Intra Uterine Insemination (IUI)
2. In Vitro Fertilization (IVF)
3. Embryo Transfer (ET)

Question 8.
Explain intra-fallopian transfer (GIFT).
Answer:
In this technology, the ovum collected from a donor is transferred into the fallopian tube of the recipient. The transferred eggs are placed with the sperms in the fallopian tube for fertilization. The fertilized egg/zygote moves towards the uterus and gets implanted in the inner lining of the uterus.

Question 9.
What is surrogacy? Explain it briefly.
Answer:
Surrogacy is a method of assisted reproduction or an agreement whereby a woman agrees to carry a pregnancy for another person, who will become the parent of the new born child after birth. The embryos are produced through in vitro fertilization in the lab and are transferred into the uterus of a surrogate mother.

Long answer questions

Question 1.
Describe the different natural methods of birth control.
Answer:
The natural method of birth control is used to prevent the meeting of eggs with sperm.
These methods include the Rhythm method (safe period), coitus interruptus, continuous abstinence, and lactational amenorrhoea.

1. Rhythm method: In the menstrual cycle, ovulation occurs at about the 14th day and the ovum survives for about two days, whereas in the female reproductive tract, the sperms remain alive for about 72 hrs. If the coitus takes place avoiding this time, the fertilization may not take place.
2. Continuous abstinence: It is the simplest and most reliable method to avoid pregnancy. In this, it is better not to have coitus for a defined period that facilitates conception.
3. Coitus interruptus: It is the oldest family planning method, in which the male partner withdraws his penis before ejaculation, preventing the deposition of semen into the vagina.
4. Lactational amenorrhoea: After parturition, the menstrual cycle resume as early as 6-8 weeks. But during breastfeeding, the menstrual cycle is delayed for about six months due to lactational amenorrhoea. During the breastfeeding period, the sucking by the baby stimulates the pituitary to secrete more prolactin hormone in order to increase milk production. This increased concentration of prolactin in the blood suppresses the release of Gonad Stimulating Etormone from the hypothalamus, which in turn prevents the gonadotropin secretion from the pituitary, resulting in the prevention of the menstrual cycle.

Question 2.
Explain intrauterine devices (IUDs).
Answer:
Intrauterine devices are the materials inserted in the uterus through the vagina by medical experts, in order to prevent pregnancy. It is one of the popular methods of birth control with a success rate of 95 to 99% in India. These devices include

1. Copper releasing IUDs
2. Hormone releasing IUDs and
3. Non-medicated IUDs. IUDs increase phagocytosis of sperm within the uterus and are the ideal contraceptive for women.

(i) Copper releasing IUDs: Copper releasing IUDs are CuT-380A, NovaT, Cae7, CuT 380 Ag, Multiload 375 etc., and they differ from each other by the amount of copper they release as free copper or copper salts into the uterus and prevent sperm motility. They can remain in the uterus for five to ten years.
(ii) Hormone releasing IUDs:
releasing IUDs are progestagen and ING – 20, which are often called as intrauterine systems (IUS). They prevent sperms from entering the cervix by increasing the viscosity of the cervical mucus.
(Hi) Non-medicated IUDs: They are made up of stainless steel or plastic. Double ‘S’ shaped plastic lippes loop is a typical example of a non-medicated IUD.

Question 3.
Describe the method of surgical sterilization.
Answer:
Surgical sterilization methods are permanent birth control methods known as vasectomy in males and tubectomy in females. They block the transport of gametes and prevent fertilization.
(i) Vasectomy: Vasectomy is the male sterilization through a surgical procedure. In this, both the vas deferens are cut and tied through a small incision on the scrotum in order to prevent the entry of sperm into the urethra. Hence the discharge from the penis has no sperms and has no chance of fertilization.
(ii) Tubectomy: The tubectomy is the surgical sterilization in females, in which a small portion of fallopian tubes is cut and tied up through a small incision in the abdomen or through the vagina. This prevents the entry of eggs into the uterus as well as fertilization.

Question 4.
What is cervical cancer? Explain its causes and preventions.
Answer:
Cervical cancer is the abnormal growth of cervical cells or cervical dysplasia, caused by a sexually transmitted virus namely Human Papilloma Virus (HPV).
The Pelvic pain, increased vaginal discharge and abnormal vaginal, bleeding are the symptoms of cervical cancer. Prolonged use of contraceptive pills and having multiple sexual partners are the major risk factors.
Cervical cancer can be diagnosed by a PAP smear (Papanicolaou smear) combined with an HPV test. The stages of cancer can be detected by X-ray, CT scan, MRI and PET scan. Radiotherapy, surgery, and chemotherapy are the options of treatment for cervical cancer.
The precancerous changes in the cervical region can be detected by modem screening techniques and therefore cervical cancer screening can be done for women above 30 years of age once a year. Now vaccination to prevent cervical cancer is available and the HPV vaccination can be given to girls aged between 9-13 years before they attain puberty. Cervical cancer can be prevented by modifications in lifestyle such as having a healthy diet, avoiding tobacco usage, preventing early marriages, practicing monogamy, and regular exercise.

Question 5.
Describe the method of In Vitro Fertilization (IVF).
Answer:
In vitro fertilization is the procedure in which sperm and eggs are allowed to fertilize outside the body in the laboratory. After fertilization, one or more fertilized eggs are introduced into the uterus of a woman, where they may implant in the wall of the uterus and develop. The excess fertilized eggs can be preserved for future use through cryopreservation. This technique was first used to treat women with blocked, damaged, or absent fallopian tubes. Nowadays this technique is used to treat many cases of infertility. The basic steps involved in IVF treatment include ovarian stimulation, egg retrieval, fertilization, embryo culture, and embryo transfer.
After 34 to 37 hrs of hCG (human chorionic gonadotropin) injection, an egg from the ovary is retrieved by minor surgery under anesthesia, using an ultrasound guide. Eggs are prepared by stripping from the surrounding cells. At the same time, sperm preparation is also carried out in special media. For each egg, 10000 – 1,00,000 sperms are needed and the eggs and sperms are brought together for fertilization. The fertilized egg or the zygote is then allowed to divide and form 8 celled blastomere, which is transferred into the uterus for further growth.
The embryo transfer technique is the transfer of an embryo with more than 8 celled blastomere stage into the uterus.

Choose the correct answers.

1. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
Answer:
(b) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)

2. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

3. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
Answer:
(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)

4. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
Answer:
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)

5. In which year Family planning programme was initiated:
(a) 1957
(b) 1962
(c) 1951
(d) 1953
Answer:
(c) 1951

6. An ideal contraceptive should be:
(a) User friendly
(b) Easily available
(c) With least side effect
(d) All the above
Answer:
(d) All the above

7. When is Justice Verma committe instituted?
(a) 2011
(b) 2016
(c) 2013
(d) 2003
Answer:
(c) 2013

8. W uch of the following is sexually transmitted disease?
(a) Elephantiasis
(b) Hepatitis B
(c) Gonorrhoea
(d) Liver cirrhosis
Answer:
(c) Gonorrhoea

9. Choose the odd man out:
(a) Gonorrhoea
(b) Chlamydiasis
(c) Candidiasis
(d) Lymphogranuloma venereum
Answer:
(c) Candidiasis

10. Find the odd one out:
(a) Rhythm method
(b) Copper IUD
(c) LNG 20
(d) Condom
Answer:
(a) Rhythm method

11. Indicate the odd one out:
(a) Ultra sound scanning
(b) Amniocentesis
(c) Foetoscope
(d) Mammogram
Answer:
(d) Mammogram

12. Choose the odd one out:
(a) Continuous abstinence
(b) Melting suppositories
(c) Coitus interruptus
(d) Lactational Amenorrhoea
Answer:
(b) Melting suppositories

13. Choose the correct pair:

Answer:
(c)

14. Indicate the incorrect pair:


Answer:
(d)

15. Choose the correct pair:

Answer:
(a)

16. Choose the incorrect pair:

Answer:
(c)

17. Assertion: Creating awareness and providing medical assistance to people can build a healthy society.
Reason: Introducing sex education in schools provides information about adolescence among school children.
(a) Both Assertion and Reason are true, the reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are true, the reason is not the correct explanation of assertion.
(c) Assertion is false, Reason is true.
(d) Assertion is true, Reason is false
(e) Both Assertion and Reason are false.
Answer:
(b) Both Assertion and Reason are true, the reason is not the correct explanation of assertion.

18. Assertion: Increased health facilities and better living conditions have enhanced longivity.
Reason: Because they have reduced the mortality due to disease and other living conditions.
(a) Both Assertion and Reason are true, the reason is the correct explanation of assertion.
(b) Both Assertion and Reason are true, the reason is not the correct explanation of assertion.
(c) Assertion is false, Reason is true.
(d) Assertion is true, Reason is false
(e) Both assertion and Reason are false.
Answer:
(a) Both Assertion and Reason are true, the reason is the correct explanation of assertion.

19. Assertion: Oral pills are used to prevent ovulation by inhibiting the secretion of FSH and LH hormones.
Reason: It contains synthetic Gonad Stimulating Hormones.
(a) Both Assertion and Reason are true, the reason is the correct explanation of assertion.
(b) Both Assertion and Reason are true, the reason is not the correct explanation of assertion.
(c) Assertion is false, Reason is true.
(d) Assertion is true, Reason is false.
(e) Both Assertion and Reason are false.
Answer:
(d) Assertion is true, Reason is false.

20. Assertion: Cervical cancer is caused by a sexually transmitted HIV virus.
Reason: The risk factors for cervical cancer include having sex with multiple unknown partners and prolonged use of contraceptive pills.
(a) Both Assertion and Reason are true, the reason is the correct explanation of assertion.
(b) Both Assertion and Reason are true, the reason is not the correct explanation of assertion.
(c) Assertion is false, Reason is true.
(d) Assertion is true, Reason is false.
(e) Both Assertion and Reason are false.
Answer:
(c) Assertion is false, Reason is true.

21. Which of the following statement is true?
(a) The sexually transmitted disease, syphilis is caused by a bacteria called Clamidia trachomatis.
(b) Syphilis is caused by a virus.
(c) Syphilis is due to fungal infection.
(d) All the above are not correct.
Answer:
(d) All the above are not correct.

22. Choose the incorrect statement:
(a) Diaphragms are made up of rubber.
(b) Diaphragms are one of the natural birth control methods.
(c) Saheli is a contraceptive pill developed by Central Drug Research Institute, Lucknow.
(d) None of the above.
Answer:
(b) Diaphragms are one of the natural birth control methods.

23. Indicate the correct statement:
(a) Amniocentesis is a prenatal technique used to detect any chromosomal abnormalities in the foetus.
(b) Amniocentesis is used to measure heart rate of foetus in the uterus.
(c) Amniocentesis is used to measure the kidney function in foetus.
(d) Amniocentesis is used to measure blood flow from mother to foetus.
Answer:
(a) Amniocentesis is a prenatal technique used to detect any chromosomal abnormalities in the foetus.

24. Which of the following statement is wrong?
(a) Ovulation occurs at about 14th day of normal menstrual cycle.
(b) The ovum survives for about 2 days.
(c) Sperm remains alive for about 48 hrs in the female reproductive tract.
(d) None of the above.
Answer:
(c) Sperm remains alive for about 48 hrs in the female reproductive tract.

Students get through the TN Board 12th Bio Zoology Important Questions Chapter 2 Human Reproduction which is useful for their exam preparation.

TN State Board 12th Bio Zoology Important Questions Chapter 2 Human Reproduction

Very short answer questions

Question 1.
Define Gametogenesis.
Answer:
Gametogenesis is defined as a process, through which the formation of male and female gametes are produced.

Question 2.
Name two reproductive hormones secreted by the pituitary gland.
Answer:

1. Follicle Stimulating Hormone (FSH).
2. Luteinizing Hormone (LH).

Question 3.
Define organogenesis.
Answer:
Organogenesis is a series of events through which the formation of specific tissues, organs, and organ systems from three germ layers takes place.

Question 4.
What are Sertoli cells? Explain its functions.
Answer:
Sertoli cells are one of the two types of cells of the seminiferous tubule. It provides nourishment to the sperm till maturation. It also secretes a hormone namely inhibin, which is involved in the negative feedback control of sperm production.

Question 5.
Leydig cells are endocrine in nature. Justify.
Answer:
Leydig cells are endocrine in nature because they secrete a hormone, androgens namely testosterone, which initiates the process of spermatogenesis.

Question 6.
Name the accessory ducts associated with the male reproductive system.
Answer:

1. Rete testis.
2. Vasa efferentia.
3. Epididymis.
4. Vas deferens.

Question 7.
Explain the function of the seminal vesicle.
Answer:
Seminal vesicles secrete an alkaline fluid, containing fructose sugar, ascorbic acid, prostaglandins. It also secretes a coagulating enzyme called vesiculate, which helps in sperm motility.

Question 8.
Mention the female accessory reproductive organs.
Answer:

1. Fallopian tube.
2. Uterus.
3. Vagina.

Question 9.
What are the three layers of the uterus wall?
Answer:
The wall of the uterus has three layers of tissue namely the perimetrium, myometrium, and endometrium.

Question 10.
Explain the functions of the skene’s gland.
Answer:
The skene’s glands are present on the anterior wall of the vagina, surrounding the lower end of the urethra. These glands secrete a lubricating fluid.

Question 11.
Define spermiogenesis.
Answer:
Spermiogenesis is a process in which a spermatid is transformed into spermatozoa or sperms.

Question 12.
Explain the term mitochondrial spiral.
Answer:
Mitochondrial spiral is the spirally twisted mitochondria around the axial filament of the middle piece of sperm.

Question 13.
What are the phases of the menstrual cycle?
Answer:

1. Menstrual phase
2. Follicular phase
3. Ovulatory phase
4. Luteal or secretory phase.

Question 14.
Explain briefly about LH surge.
Answer:
In the middle of the ovulatory phase, maximum secretion of LH, known as LH surge takes place. This in term induces the rupture of the Graafian follicle, resulting in the release of the ovum from the ovary wall into the peritoneal cavity.

Question 15.
What is meant by menopause?
Answer:
Menopause is a phase, in which ovulation and menstruation stop in a woman’s life.

Question 16.
Explain the morula stage.
Answer:
The morula stage of the human embryo in which a loose collection of cells into a berry-shaped cluster of 16 or more cells is formed after 72 hours of fertilization.

Question 17.
Define monozygotic twins.
Answer:
When a single fertilized egg splits into two during the first cleavage, each daughter egg develops into each individual forming identical twins.

Question 18.
Define parturition.
Answer:
Parturition is the completion stage of pregnancy and childbirth.

Question 19.
What is colostrum?
Answer:
Colostrum is a yellow fluid secreted by the mammary gland during the initial few days after parturition.

Question 20.
Expand the following abbreviations:
Answer:
(i) WABA,
(ii) WHO,
(i) WABA: World Alliance for Breastfeeding Action.
(ii) WHO: World Health Organisation.

Short answer questions

Question 1.
What is the constitution of the seminiferous tubule?
Answer:
The seminiferous tubule is made up of two types of stratified epithelium namely Sertoli cells or nurse cells and spermatogenic cells or male germ cells. Sertoli cells are elongated and pyramidal cells, which nourish the growing sperm. They also secrete a hormone namely inhibin, which is responsible for the negative feedback control of sperm production. Spermatogenic cells form the spermatozoa by meiosis or reduction division.

Question 2.
Distinguish between Sertoli cells and Leydig cells.
Answer:

Sertoli cells	Leydig cells
Sertoli cells are elongated and pyramidal cells.	Embedded in soft connective tissue surrounding the seminiferous tubule.
They provide nourishment to the sperms till maturation.	They are endocrine in nature.
They secrete a hormone called inhibin, which is responsible for the negative feedback control of sperm production.	They secrete androgens, namely the testosterone which is responsible for the initiation of the process of spermatogenesis.

Question 3.
Write down the functions of the accessory glands of the male reproductive system.
Answer:
The accessory glands of the male reproductive system are:

1. Seminal vesicle.
2. Bulbourethral gland or Cowper’s gland.
3. Prostate gland.

Seminal vesicles:
secrete seminal plasma having fructose sugar, ascorbic acid, prostaglandins, and a coagulating enzyme, namely vesiculase, which helps sperm motility. The seminal plasma is alkaline in nature.
Bulbourethral glands: They secrete a lubricating fluid and helps in the lubrication of the penis.
Prostate gland: It secretes a slightly acidic fluid containing citrate, several enzymes, and prostate-specific antigens.

Question 4.
Explain the structure of the penis.
Answer:
The penis is a male copulatory organ, made up of special tissues which facilitate the erection of the penis to deliver the seminal fluid in the vagina of the female. The enlarged end of the penis is called the glans penis. It is covered by a loose fold of skin called foreskin or prepuce. The structure of the penis facilitates insemination.

Question 5.
Describe the structure of Uterus.
Answer:
The Uterus is otherwise called a womb, which is an inverted pear-shaped structure. It is a hollow thick-walled and highly vascularized structure lying between the urinary bladder and the rectum in the pelvic cavity. The body of the uterus occupies the major portion and the fundus is the rounded region superior to it.
Cervix is the narrow opening of the uterus into the vagina. The external orifice and internal orifice through which the cervical canal opens communicates with the vagina and with the uterus respectively. The birth canal is formed by the cervical canal and vagina.

Question 6.
Distinguish between Bartholin’s glands and skene’s glands.
Answer:

Bartholin’s glands	Skene’s glands
These glands are located posterior to the left and right of the opening of vagina.	These glands are seen on the anterior wall of the vagina and the lower end of the urethra.
They secrete lubricating mucus and are homologous to the bulbourethral glands of the males.	They also secrete a lubricating fluid and are homologous to the prostate gland of males.

Question 7.
Explain briefly the normal development of the breast.
Answer:
The normal development of breasts in females takes place at puberty and progresses with changes in each menstrual cycle. The breast size is mainly due to fat deposits. The glandular structure is underdeveloped in a non-pregnant women. In pregnant women, the glandular structure develops. The efficiency of lactation does not have any influence on the size of the breast.

Question 8.
Name the important hormones involved in spermatogenesis.
Answer:

1. Gonadotropin-Releasing Hormone (GnRH).
2. Follicle Stimulating Hormone (FSH).
3. Luteinizing Hormone (LH).

Question 9.
Write down the events in the follicular phase of the menstrual cycle.
Answer:
The follicular phase of the menstrual cycle extends from the 5th day of the cycle until the time of ovulation. During this phase, a fully mature Graafian follicle is formed from the primary follicle in the ovary. Simultaneously, the endometrium regenerates through proliferation. The secretion of FSH and LH during this phase induces these changes in the ovary and uterus. The follicular cells secrete oestrogen during this phase.

Question 10.
What is meant by implantation?
Answer:
The fertilized egg undergoes cleavage and forms a fluid-filled hollow ball of about 100 cells, called the blastocyst. Under the influence of progesterone, the embryo moves through the fallopian tube into the uterine cavity and becomes embedded in the endometrium of the uterus and this process is called implantation.

Question 11.
Name the hormones secreted by the placenta during pregnancy.
Answer:

1. Human Chorionic Gonadotropin (HCG).
2. Human Chorionic Somatomammotropin (HCS) or Human Placental Lactogen (HPL).
3. Oestrogens and Progesterone.

Question 12.
What is meant by Polycystic Ovary Syndrome (PCOS).
Answer:
PCOS is a complex endocrine disorder. This affects women in their reproductive phase of the year.
This is mainly due to the formation of many partially formed follicles which contain an egg each. These eggs do not grow to maturity and take part in fertilization. The symptoms of this syndrome include irregular menstrual cycles, increased androgen levels, excessive facial and body hair growth, acne, obesity, reduced fertility, and increased risk of diabetes.

Long answer questions

Question 1.
Write about the accessory glands of the male reproductive system.
Answer:
The accessory glands associated with the male reproductive system include the following:
(a) A paired seminal vesicles.
(b) Bulbourethral glands or Cowper’s glands.
(c) A single prostate gland.

1. Seminal vesicles: Seminal vesicles are located on either side of the prostate gland and secrete an alkaline fluid called seminal plasma, which contains fructose sugar, ascorbic acid, prostaglandins, and a coagulating enzyme called vesiculates, which helps sperm motility.
2. The Bulbourethral glands: These glands are located inferior to the prostate gland and they secrete a lubricating fluid, which helps to lubricate the penis.
3. The prostate glands: The single prostate gland is placed just below the urinary bladder, encircling the urethra. It secretes slightly acidic fluid, which contains citrate, several enzymes and prostate-specific antigens.
   The secretions of the three glands along with sperm is called semen or seminal fluid.

Question 2.
Draw the diagrammatic view of the female reproductive system and label the parts.
Answer:

Question 3.
Give an account of mammary glands.
Answer:
Mammary glands are modified sweat glands present in both sexes. It is functional in females and rudimentary in males. In humans, a pair of mammary glands is placed in the thoracic region. The glandular tissues and variable quantities of fat are present in mammary glands along with a median nipple. The nipple is surrounded by a pigmented area called the areola. The areolar glands, modified sebaceous glands are present on the surface. They help in reducing the cracking of the skin of the nipple.
Each mammary gland consists of 2 – 25 lobes. They are separated by fat and connective tissues. Each lobe contains many lobules, which contain acini or alveoli lined by epithelial cells. Milk is secreted by the cells of alveoli, which opens into mammary tubules. The mammary duct is formed by joining the tubules of each lobe. The mammary ampulla is formed by joining several mammary ducts. The mammary duct is connected to the lactiferous duct in the nipple. The lactiferous sinus is the expansion of the lactiferous duct under the nipple and serves as a reservoir of milk. On the surface of the nipple, each lactiferous duct opens by a minute pore.

Question 4.
Explain the sequence of events in the fertilization process in humans.
Answer:
Fertilization is a process in which a haploid male gamete fuses with a haploid ovum to form a diploid zygote.
The sperms are deposited in the female reproductive tract by copulation and sperms undergo a process called capacitation. It is a biochemical event that enables the sperm to penetrate through the egg membrane and fertilize the egg.
Fertilization of the ovum takes place only if the ovum and sperm are deposited simultaneously to the ampullary isthmic junction of the fallopian tube.
The sperm has to penetrate the multiple layers of granulosa, which are around the ovum forming corona radiata. The follicular cells are held together by hyaluronic acid, an adhesive substance. The acrosome of the sperm secretes a proteolytic enzyme, hyaluronidase, which lysis the membrane and helps the penetration of sperm through corona radiata and zona pellucida. The process is called acrosomal reaction. Once fertilization is over, a barrier membrane, the fertilization membrane around the ovum is formed by the cortical granules from the cytoplasm of the ovum. This membrane prevents further entry of other sperms. Thus polyspermy is prevented.

Choose the correct answers.

Question 1.
Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)

Question 2.
Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(iii); (r)-(iv); (s)-(i)
(d) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
Answer:
(c) (p)-(ii); (q)-(iii); (r)-(iv); (s)-(i)

Question 3.
Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(i); (r)-(iv); (s)-(ii)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

Question 4.
Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
Answer:
(d) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

Question 5.
Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(d) (p)-(iii); (q)-(i); (r)-(iv); (s)-(ii)
Answer:
(b) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)

Question 6.
The fusion of male and female gametes is called as:
(a) Oogenesis
(b) Fertilization
(c) Gastrulation
(d) Spermiation
Answer:
(b) Fertilization

Question 7.
The hormone inhibin is secreted by:
(a) Pituitary
(b) Leydig cells
(c) Sertoli cells
(d) Endometrium
Answer:
(c) Sertoli cells

Question 8.
The bulbourethral gland is otherwise called as:
(a) Prostate gland
(b) Seminal vesicle
(c) Cowper’s gland
(d) Skene’s gland
Answer:
(c) Cowper’s gland

Question 9.
The mammary glands are modified:
(a) Sebaceous glands
(b) Green glands
(c) Sweat glands
(d) Bartholin’s gland
Answer:
(c) Sweat glands

Question 10.
The acrosomal membrane disintegrates by the proteolytic enzyme called:
(a) Leutinising hormone
(b) Hyaluronidase
(c) Lactogenase
(d) Prolactin
Answer:
(b) Hyaluronidase

Question 11.
Choose the odd man out:
(a) human Chorionic Gonadotropin
(b) Follicle Stimulating Hormone.
(c) human Chorionic Somatomammotropin
(d) human Placental Lactogen.
Answer:
(b) Follicle Stimulating Hormone.

Question 12.
Choose the odd one.
(a) Seminal vesicle
(b) Prostate gland
(c) Cowper’s gland
(d) Bartholin’s gland
Answer:
(d) Bartholin’s gland

Question 13.
Indicate the odd one.
(a) Gametogenesis
(b) Spermiogenesis
(c) Spermatogenesis
(d) Oogenesis
Answer:
(b) Spermiogenesis

Question 14.
Choose the odd man out.
(a) Hyaluronidase
(b) FSH – Follicle Stimulating Hormone
(c) LH – Lutenizing Hormone
(d) ABP – Androgen Binding Protein
Answer:
(a) Hyaluronidase

15. Find out the odd one.
(a) Labia majora
(b) Labia minora
(c) Zona pellucida
(d) Hymen
Answer:
(c) Zona pellucida

16. Choose the correct pair.

Answer:
(b)

17. Which of the following pair is wrong?

Answer:
(c)

18. Choose the correct pair.

Answer:
(d)

19. Choose the incorrect pair.

Answer:
(a)

20. Which of the following is the correct pair?

Answer:
(b)

21. Assertion: Leydig cells surrounding the seminiferous tubules are endocrine in nature.
Reason: They secrete testosterone hormone which initiates the process of spermatogenesis.
(a) Assertion and Reason are true, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are true, Reason is not the correct explanation of Assertion.
(c) Assertion is true, Reason is false.
(d) Both Assertion and Reason are false.
Answer:
(a) Assertion and Reason are true, Reason is the correct explanation of Assertion.

22. Assertion: The seminal vesicles secrete a slightly acidic fluid called seminal plasma.
Reason: Seminal plasma helps in the movement of the sperm.
(a) Assertion and Reason are true, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are true, Reason is not the correct explanation of Assertion.
(c) A is true, Reason is false.
(d) Both Assertion and Reason are false.
Answer:
(d) Both Assertion and Reason are false.

23. Assertion: The medulla of the ovarian stroma is a loose connective tissue with abundant blood vessels, lymphatic vessels and nerve fibres.
Reason: in the medulla, the various stages of ovarian follicles are present.
(a) Assertion and Reason are true, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are true, Reason is not the correct explanation of Assertion.
(c) Assertion is true, Reason is false.
(d) Both Assertion and Reason are false.
Answer:
(c) Assertion is true, Reason is false.

24. Assertion: Acrosome is a small cup-like pointed structure at the tip of the nucleus of sperm, which helps the sperm to penetrate the ovum during fertilization.
Reason: Acrosome contains a proteolytic enzyme, hyaluronidase popularly known as sperm lysin which helps to penetrate the ovum during fertilization.
(a) Assertion and Reason are true, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are true, Reason is not the correct explanation of Assertion.
(c) Assertion is true, Reason is false.
(d) Both Assertion and Reason are false.
Answer:
(a) Assertion and Reason are true, Reason is the correct explanation of Assertion.

25. Assertion: During the luteal phase of the menstrual cycle, the Graafian follicle is transformed into a transitory endocrine gland called the corpus luteum.
Reason: Corpus luteum secretes a large amount of Oestrogen, which is essential for the maintenance of the endometrium.
(a) Assertion and Reason are true, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are true, Reason is not the correct explanation of Assertion.
(c) Assertion is true, Reason is false.
(d) Both Assertion and Reason are false.
Answer:
(c) Assertion is true, Reason is false.

26. Which of the following a correct statement?
(a) At the end of gametogenesis in females, each primary Oocyte gives rise to only one haploid ovum.
(b) At the end of gametogenesis in females, each primary Oocytes gives rise to four haploid ovum.
(c) At the end of gametogenesis in females, each primary Oocyte gives rise to three polar bodies and two ovum.
(d) None of the above.
Answer:
(a) At the end of gametogenesis in females, each primary Oocyte gives rise to only one haploid ovum.

27. Choose the incorrect statement:
(a) Human ovum is non-cleidoic in nature.
(b) Human ovum is alecithal in nature.
(c) Human ovum contains a small nucleus in the cytoplasm.
(d) Human ovum is microscopic in nature.
Answer:
(c) Human ovum contains a small nucleus in the cytoplasm.

28. Indicate the correct statement:
(a) The Acrosome of sperm possess nebenkem.
(b) The middle piece of sperm contain a mitochondrial spiral.
(c) The proximal centriole of sperm gives rise to the axial filament.
(d) None of the above.
Answer:
(b) The middle piece of sperm contain a mitochondrial spiral.

29. Choose the incorrect statement:
(a) Inhibin is a hormone involved in the negative feedback control of sperm production.
(b) Leydig cells are endocrine in nature.
(c) Vesiculase enzyme is a proteolytic enzyme.
(d) Corpus luteum secretes lot of progesterone.
Answer:
(c) Vesiculase enzyme is a proteolytic enzyme.

30. Which of the following is a correct statement?
(a) Mammary glands are modified sebaceous glands.
(b) It is functional in males and rudimentary in females.
(c) Mammary glands are modified sweat gland.
(d) None of the above.
Answer:
(c) Mammary glands are modified sweat gland.

Students get through the TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms which is useful for their exam preparation.

TN State Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms

Very short answer questions

Question 1.
Define binary fission.
Answer:
Binary fission is the process, in which the parent organism divide into two halves and each half grows into a daughter individual. Eg: Amoeba.

Question 2.
Mention any two types of binary fission.
Answer:

1. Transverse binary fission.
2. Longitudinal binary fission.

Question 3.
What type of binary fission is seen in dinoflagellates? Explain briefly.
Answer:
The asexual reproduction seen in dinoflagellates is through oblique binary fission, in which the plane of division is oblique.

Question 4.
Define strobilation.
Answer:
Strobilation is a special type of transverse fission, in which several transverse fission occur simultaneously, resulting in a number of individuals. Eg: Aurelia.

Question 5.
Define plasmogamy.
Answer:
Plasmotomy is the reproductive process in which the division of multinucleated parent into many multinucleate daughter individuals with the division of nuclei.

Question 6.
Explain briefly about gemmules.
Answer:
Gemmules are the endogenous buds produced by freshwater sponges for asexual reproduction.

Question 7.
Define archetypes.
Answer:
Archeocytes are the fully grown gemmules and are hard ball-like structures consisting of an internal food-laden mass, seen in freshwater sponges.

Question 8.
Mention briefly about fragmentation type of reproduction.
Answer:
In fragmentation type of asexual reproduction, the parent body breaks into many pieces, and each piece has the potential to grow into a new individual.

Question 9.
Define apolysis.
Answer:
Apolysis is the process in which the gravid proglottids of Taenia solium are regularly detached either singly or in groups from the posterior end.

Question 10.
Explain hologamy.
Answer:
Hologamy is the type of sexual reproduction in lower organisms, in which the entire mature organisms acts as gamete and fusion of such gametes takes place.
Eg: Trichonympha.

Question 11.
Define parthenogenesis.
Answer:
Parthenogenesis is defined as the development of an egg into a complete individual without fertilization.

Question 12.
What is meant by paedogenesis?
Answer:
Paedogenesis is the process in which the larvae produce a new generation of larvae through parthenogenesis. Eg: Larvae of Gall fly.

Question 13.
Define Ovoviviparous.
Answer:
Ovoviviparous animals are those animals in which the embryo develops inside the egg, which remains in the body of mother until they are ready to hatch. Eg: Shark.

Question 14.
Explain restorative regeneration.
Answer:
Restorative regeneration is the process of regeneration, in which restoration of the entire part of organisms, which is severed. Eg: The tail of the wall lizard.

Question 15.
Mention the two types of regeneration.
Answer:

1. Morphallaxis
2. Epimorphosis

Short answer questions

Question 1.
Mention the different modes of asexual reproduction.
Answer:
The different modes of asexual reproduction seen in animals are fission, sporulation, budding, gemmule formation, fragmentation, and regeneration.

Question 2.
Distinguish between binary fission and multiple fission.
Answer:

Binary fission	Multiple fission
In binary fission the parent organism. divides into two halves and each half grows into a daughter individual.	In multiple fission the parent organism divides into many similar daughter cells.
The nucleus divides first, followed by division of cytoplasm.	The nucleus divides first repeatedly without division of cytoplasm and later the cytoplasm divides as many times as that of nuclei.
Two daughter individuals are fomiec after a division.	Many daughter organisms are formed.

Question 3.
Explain the type of multiple fission in Plasmodium.
Answer:
In Plasmodium, multiple fission occurs in its two stages namely schizont and oocyte stage. In the schizont stage, the process of multiple fission is called schizogony and the offsprings are known as merozoites. In the oocyte stage, multiple fission occurs by sporogony, and the offsprings are called sporozoites.

Question 4.
Distinguish between strobilation and sporulation.
Answer:

Strobilation	Sporulation
Strobilation is process in which several transverse fission occur simultaneously resulting in a number of individuals.	Amoeba multiples by sporulation during unfavourable conditions, without encystment.
It is seen in some metazoan animals like Aurelia.	Nucleus breaks into small fragments called chromatin blocks. Each fragment develops a nuclear membrane, which is surrounded by cytoplasm, forming a spore case around it.

Question 5.
Explain the exogenous type of budding with an example.
Answer:
Exogenous budding is one type of asexual reproduction, in which the buds are formed on the outer surface of the parent body.
Eg: Hydra.
In Hydra, when food is plenty, a small elevation on the outer surface of the body is formed by the increase of ectoderm cells. Then ectoderm and endoderm are pushed out to form a bud. The bud develops an interior lumen in continuation with the gastrovascular cavity of the parent. Subsequently, the bud develops mouth and tentacles at the free end. When it is grown fully, a constriction develops at the base of the bud and finally, it detaches from the parent to lead an independent life.

Question 6.
Draw and label the structure of a gemmule of sponge.
Answer:

Question 7.
Distinguish between fragmentation and regeneration.
Answer:

Fragmentation	Regeneration
Fragmentation is the process in which the parental body breaks into many fragments and each fragment has the potential to grown into a new individual.	Regeneration is the growth of injured region. In morphallaxis. the whole body grows from a small fragment. Eg: Planuria.
This type of reproduction occurs in sea anemone.	In epimorphosis, the severed part or tissue is restored by regeneration. Eg: Lizard.

Question 8.
Mention the three types of sexual reproduction in animals for example.
Answer:

1. Oviparous – Reptiles and Aves
2. Viviparous – Mammals
3. Ovoviviparous – Shark.

Question 9.
Name the three types of natural parthenogenesis.
Answer:

1. Arrhenotoky – Honey bees
2. Thelytoky – Solenobia
3. Amphitoky – Aphis.

Question 10.
Name any three animals, whose eggs are without calcareous shells.
Answer:

1. Carp
2. Frog
3. Catfish

Long answer questions

Question 1.
What are the types of binary fission? Explain each with an example.
Answer:
There are four types of binary fission namely

1. Simple irregular binary fission
2. Transverse binary fission
3. Longitudinal binary fission
4. Oblique binary fission.

Simple binary fission: This type of binary fission is present in irregularly shaped organisms like Amoeba. Before division, the contractile and nucleolus disappear. The nucleus divides mitotically followed by the division of the cytoplasm through making a constriction in the middle. The daughter cells are formed.
Transverse binary fission: In this, the division takes place along the transverse axis of the individual. The macronucleus divides by amitosis and the micronucleus divides by mitosis.
Eg: Paramecium andplanaria.
Longitudinal binary fission: In this type of fission, the organism divides in the longitudinal axis. Eg: Flagellates when the cell divides longitudinally, one of the daughter cells retains the flagellum. The other daughter cell develops a new flagellum from the new basal granule.
Eg: Vorticella and Euglena.
Oblique binary fission: In this type, the division takes place on the plane of oblique. Eg: Ceratium.

Question 2.
Describe the process of budding in Hydra.
Answer:
In Hydra, the exogenous type of budding takes place. Under the favourable condition, i.e., when plenty of food is available, the ectoderm cells divide and increase in number. They form a small elevation on the body surface. This leads to the formation of bud by pushing ectoderm and endoderm outside. The bud then develops an internal lumen, which is continuous to the gastrovascular cavity of the parent. The bud grows larger and develops a mouth and tentacles at the free end. When it is fully grown, a constriction and developed at the base of the bud finally detaches from the parent body. Each detached bud leads an independent life.

Question 3.
Explain the types of regeneration with suitable example.
Answer:
Abraham Trembley was the first scientist to demonstrate regeneration in Hydra. Regeneration is the process of regrowth of injured tissue or part of the organism. There are two types of regeneration namely morphallaxis and epimorphosis. In morphallaxis, a small fragment of the parent body grows into a whole body. Eg: Hydra and planaria. When planaria are accidentally cut into many pieces, each piece can regenerate lost part and forms the whole body. The parts usually retain their original polarity. The portion with basal discs develops oral ends with mouth and tentacles and the oral portion generate the basal disc in Hydra.
Epimorphosis is the replacement of lost body parts. It is of two types namely reparative and restorative regeneration. In reparative regeneration, only certain damaged tissue can be regenerated, whereas in restorative regeneration, the detached body part can be regenerated.
Eg: Starfish, the tail of wall lizard.

Question 4.
Draw and label the events of binary fission in Amoeba and paramecium.
Answer:

Question 5.
Explain the sporulation in the amoeba with the help of a diagram.
Answer:
Amoeba multiplies by sporulation without encystments during the unfavourable condition. Chromatin blocks or fragments of the nucleus are formed by breaking of parent nucleus. Each chromatin block develops a nuclear membrane, surrounded by a layer of cytoplasm. This forms a spore-case around it. When the conditions become favourable, the spores are liberated after the disintegration of the parent body. Each spore forms a young amoeba.

Choose the correct answers.

1. Match the following:


(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

2. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(n); (q)-(i); (r)-(iv); (s)-(iii)
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

3. Match the following:

(a) (p)-(ii); (q)-(iii); (r)-(iv); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(a) (p)-(ii); (q)-(iii); (r)-(iv); (s)-(i)

4. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)

5. Asexual reproduction is not common in:
(a) Protista
(b) Bacteria
(c) Archaea
(d) Reptelia
Answer:
(d) Reptilia

6. Asexual reproduction through gemmule formation is found in:
(a) Aurelia
(b) Sponges
(c) Plasmodium
(d) Hydra
Answer:
(b) Sponges

7. During unfavourable multiplies by:
(a) Fragmentation
(b) Binary fission
(c) Sporulation
(d) Budding
Answer:
(c) Sporulation

8. The tail of wall lizard is regenerated by a process called:
(a) Morphallaxis
(b) Epimorphosis
(c) Reparative regeneration
(d) Restorative regeneration
Answer:
(d) Restorative regeneration

9. Choose the odd man out:
(a) Simple binary fission
(b) Transverse binary fission
(c) Multiple fission
(d) Longitudinal binary fission
Answer:
(c) Multiple fission

10. Indicate the odd one out:
(a) Strobilation
(b) Proglotids
(c) Sporulation
(d) Plasmotomy
Answer:
(b) Proglotids

11. Find out the odd one out:
(a) Autogamy
(b) Hologamy
(c) Exogamy
(d) Monogamy
Answer:
(d) Monogamy.

12. Choose the odd one in relation to reproduction:
(a) Birds
(b) Frog
(c) Shark
(d) House lizard
Answer:
(c) Shark

13. Choose the correct pair.

Answer:
(c)

14. Indicate the incorrect pair.

Answer:
(b)

15. Find out the correct pair.

Answer:
(d)

16. Choose the incorrect pair.

Answer:
(c)

17. Assertion: The offsprings produced by asexual reproduction are genetically identical.
Reason: They are produced by mitotic or amitotic cell division.
(a) Assertion is true; the reason is false.
(b) Assertion is false; the reason is true.
(c) Both assertion and reason are true.
(d) Both assertion and reason are false.
Answer:
(c) Both assertion and reason are true.

18. Assertion: In planaria, the plane of division runs along the longitudinal axis of the individual.
Reason: They are bilaterally symmetrical.
(a) Assertion is true; the reason is false.
(b) Assertion is false; the reason is true.
(c) Both assertion and reason are true.
(d) Both assertion and reason are false.
Answer:
(d) Both assertion and reason are false.

19. Assertion: During unfavourable conditions, the freshwater sponges disintegrate, but the gemmule can withstand adverse conditions.
Reason: Gemmules are hard balls consisting of an internal mass of food ladenarchaeocytes.
(a) Assertion is true; the reason is false.
(b) Assertion is false; the reason is true.
(c) Both assertion and reason are true.
(d) Both assertion and reason are false.
Answer:
(c) Both assertion and reason are true.

20. Assertion: In Taenia solium the gravid proglottids are regularly cut off either singly or in groups from the posterior end by a process called apolysis.
Reason: It helps in transferring the developed embryos from the primary host (man) to find a secondary host (pig).
(a) Assertion is true; the reason is false.
(b) Assertion is false; the reason is true.
(c) Both assertion and reason are false.
(d) Both assertion and reason are true.
Answer:
(d) Both assertion and reason are true.

21. Which of the following statement is correct?
(a) Exogenous budding is present in Paramecium.
(b) Endogenous budding is present in Euglena.
(c) Pedal laceration occurs in many genera of sea anemones.
(d) Gemmules are produced in Hydra.
Answer:
(c) Pedal laceration occurs in many genera of sea anemones.

22. Choose the incorrect statement.
(a) In some metazoan animal, a special type of transverse fission called strobilation occurs.
(b) Amoeba withdraws its pseudopodia during an increase in temperature.
(c) Plasmotomy occurs in Aurelia.
(d) During unfavourable conditions amoeba multiplies by sporulation.
Answer:
(c) Plasmotomy occurs in Aurelia.

23. Which of the following statement is wrong?
(a) Regeneration was first studied in Hydra by Abraham Trembley.
(b) Epimorphosis is the replacement of lost body parts.
(c) In morphallaxis the whole body grows from a small fragment.
(d) None of the above statements is correct.
Answer:
(d) None of the above statements is correct.

24. Indicate the correct statement.
(a) In Arrhenotoky, only females are produced by parthenogenesis.
(b) In Arrhenotoky, only males are produced by parthenogenesis.
(c) In Amphitoky, only females are produced by parthenogenesis.
(d) In Thelytoky, both male and female are produced by parthenogenesis.
Answer:
(b) In Arrhenotoky, only males are produced by parthenogenesis.

25. Which of the following statement is incorrect?
(a) In oviparous animals, the young hatch from the eggs laid outside the mother’s body.
(b) In fishes, the eggs are not covered by calcareous shells.
(c) In ovoviviparous animals the embryo develops inside the mother’s body with the placenta.
(d) Viviparous animals give rise to young ones.
Answer:
(c) In ovoviviparous animals the embryo develops inside the mother’s body with the placenta.

TN 12th Bio Zoology Important Questions State Board English Medium 2022-2023.

Biology NEET MCQ

TN State Board 12th Bio Zoology Important Questions and Answers

• Chapter 1 Reproduction in Organisms Important Questions
• Chapter 2 Human Reproduction Important Questions
• Chapter 3 Reproductive Health Important Questions
• Chapter 4 Principles of Inheritance and Variation Important Questions
• Chapter 5 Molecular Genetics Important Questions
• Chapter 6 Evolution Important Questions
• Chapter 7 Human Health and Diseases Important Questions
• Chapter 8 Microbes in Human Welfare Important Questions
• Chapter 9 Applications of Biotechnology Important Questions
• Chapter 10 Organisms and Population Important Questions
• Chapter 11 Biodiversity and its Conservation Important Questions
• Chapter 12 Environmental Issues Important Questions

Students get through the TN Board 12th Bio Botany Important Questions Chapter 10 Economically Useful Plants and Entrepreneurial Botany which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 10 Economically Useful Plants and Entrepreneurial Botany

Very short answer questions

Question 1.
What is meant by pseudo-cereal?
Answer:
Pseudo cereal refers to the foods that are prepared and eaten as a whole grain but are from grasses. Eg. Quinoa.

Question 2.
Give the scientific names of two bowls of cereal.
Answer:

1. Paddy – Oryza sativa
2. Wheat – Triticum aestivum

Question 3.
Mention any two examples of minor millets.
Answer:

1. Foxtail millet – Setaria italica.
2. Kodo millet – Paspalum scorbiculatum.

Question 4.
Define Pulses.
Answer:
Pulses are the edible seeds that are harvested from the fruits of the Fabaceae family. They ‘provide a vital source of plant-based protein, vitamins, and minerals.

Question 5.
Mention the nativity of black gram and green gram.
Answer:

1. Black gram – India
2. Green gram – India.

Question 6.
Define sugar.
Answer:
Sugar refers to the generic name of sweet tasting soluble carbohydrate that is used in foods and beverages.

Question 7.
Mention any two uses of Palmyra.
Answer:

1. Palm sugar is prepared from the exudate from the inflorescence of Palmyra.
2. Germinated seeds have elongated embryos surrounded by fleshy scale leaf, which is edible.

Question 8.
Explain briefly the property of coffee.
Answer:
Coffee, a non-alcoholic beverage, contains an alkaloid that stimulates the central nervous system. It also possess milS diuretic property.

Question 9.
What is the queen of spices? Write the areas of its cultivation in India.
Answer:
The queen of spices is cardamom. It is cultivated in the Western Ghats and North-Eastern India.

Question 10.
What is meant by red pepper?
Answer:
The red pepper is otherwise called as chilies and used in the preparation of sauces, curry powder, and pickles. The active ingredient is capsaicin.

Question 11.
Mention any two properties of teak wood.
Answer:

1. The heartwood of teak is golden yellow to golden brown in color and changes into darker when exposed to light.
2. It is durable, as it is resistant to the attack of termites and fungi.

Question 12.
Who invented paper production?
Answer:
Paper production is a Chinese invention. They prepared paper from the inner bark of paper mulberry in 105 A.D.

Question 13.
What is folk medicine?
Answer:
Folk medicine refers to the system of medicine practiced by ethnic communities through oral communication without any written documents.

Question 14.
Name any two medicinal plants.
Answer:

1. Keezhanelli – Phyllanthus amarus
2. Nilavembu – Andrographis paniculata.

Question 15.
Define Entrepreneurial Botany.
Answer:
Entrepreneurial Botany is defined as the study of how new businesses are created using plant resources. Eg. the Timber industry, the Rubber industry, etc.

Short answer questions

Question 1.
Mention the uses of wheat.
Answer:

1. In the Northern part of India Wheat is the staple food.
2. Bread and other bakery products are produced from wheat flour.
3. Alcoholic beverages and nutritive drinks are made from malted wheat.

Question 2.
Distinguish between a black gram and green gram.
Answer:

Black gram	Green gram
The outer coat is black in colour.	The outer coat is green in colour.
The botanical name is Vigna mungo	The Botanical name is Vigna radiate.
Uttar Pradesh, Chaattisgarh and Karnataka are major states of cultivation.	Madhya Pradesh, Karnataka and Tamil Nadu are the major states of Cultivation.

Question 3.
What are the national fruits of India? Explain its varieties and uses.
Answer:
The national fruit of India is mango.
The major varieties of mango in India are Alphonsa, Banganapalli, Neelam, and Malkova.
Mango is rich in beta carotenes and forms major table fruit in India. Unripe mangoes are used in chutneys, pickles, side dishes, or maybe eaten raw with salt and chili. Jelly is made from mango pulp. The aerated or non-aerated soft drinks are produced from mango pulp.

Question 4.
Mention the origin and area of cultivation of sugar cane.
Answer:
Sugar cane, Saccharum officinarum is originated from New Guinea.
All districts of Tamil Nadu except Kanyakumari and Nilgiris cultivate sugar cane.

Question 5.
Write down the importance of groundnut.
Answer:
Brazil is the native of groundnut. The nuts contain 45% oil. Kernels are a rich source of phosphorous and vitamins.
It gives the premium cooking oil as it does not smoke. This oil is used in the manufacture of soaps and lubricants.

Question 6.
What is the king of spices? Mention its uses.
Answer:
The king of spices is black pepper, which is otherwise known as “Black Gold of India”. In the preparation of sauces, soups, curry powder, and pickles, it is used as a flavoring agent. It is also used in medicine as an aromatic stimulant for enhancing salivary and gastric secretions. Pepper enhances the bio-absorption of medicines.

Question 7.
List the various uses of rubber.
Answer:

1. 70% of the rubber is being consumed by tire and other automobile manufacturing companies.
2. Rubber is used in the manufacture of footwear, wire and cable insulations, raincoats, household and hospital goods, erasers, adhesives, and rubber bands. Concentrated latex is used for making gloves, balloons, and condoms. Cushion, pillows, and life belts are manufactured from foamed latex.

Question 8.
What is a psychoactive drug? Explain any one of such drugs.
Answer:
Psychoactive drug refers to a drug from some plants, which alters an individual’s perceptions of mind by producing hallucination.
One of the examples is cannabis or marijuana, the botanical name being Cannabis sativa. Marijuana is native of China and now it is legally cultivated in the states of Gujarat, Himachal Pradesh, Uttarkhand, Uttar Pradesh, and Madhya Pradesh of India as industrial hemp. The active principle, which possesses medicinal properties is trans- tetrahydro cannabinol (THC).

Long answer questions

Question 1.
Write down the attributes of cereals as food plants?
Answer:

1. Their greater adaptability and successful colonization on every type of habitat.
2. The relative ease of cultivation is another important quality of cereals.
3. They produce a higher yield per unit area due to their tillering property.
4. The grains can be easily handled because the grains are dry and compact. They can easily be transported and stored without spoilage.
5. They provide energy to the consumer due to their high calorific value.

Question 2.
Write about the importance of vegetables with examples.
Answer:
Vegetables are an important part of healthy eating. They provide many nutrients, including vitamins, potassium, fiber and folic acid. Vitamins A, E and C are abundant is vegetables.
One of the examples of a vegetable is okra, Abelmoschus esculantus. It is otherwise known as Lady’s finger, which is a native of tropical Africa. Lady’s finger is grown in Assam, Maharashtra, and Gujarat in large quantities. In Tamil Nadu, Coimbatore, Dharmapuri, and Vellore are the major districts, which cultivate okra.
The fresh and tender fruits are used as vegetables. It has the most important nutrients, especially phosphorous.

Question 3.
List out the uses of red chilies.
Answer:

1. Red chilies are crushed and powdered to use as condiments.
2. Chilies are used in the manufacture of sauces, curry powders, and preparation of pickles.
3. The active ingredient of chilies is capsaicin.
4. It has pain-relieving properties and used in pain-relieving balms.
5. Chillies are a good source of vitamins C, A, and E.

Question 4.
Write about the folk system of medicine.
Answer:
The rural communities of India are practicing this system of medicine through oral tradition without any authenticated written documents. Ministry of Environment and Forestry launched a program of All India Coordinated Research project on ethnobotany to document the plants used as medicine by ethenic groups in India. About 8000 plant species have been documented as the result of this project.
Irulas, Malayalis, Kurumbas, Paliyans, and Kannis are the tribal groups in Tamil Nadu, who are known for their medicinal knowledge. Some of the important medicinal plants they use include keezhanelli and nilavembu, which are now brought for medicinal use.

Choose the correct answers.

1. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)
(c) (p)-(ni); (q)-(iv); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(b) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)

2. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

3. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
Answer:
(a) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)

4. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(d) (p)-(ii); (q)-(i); fr)-(iv); (s)-(iii)
Answer:
(d) (p)-(ii); (q)-(i); fr)-(iv); (s)-(iii)

5. Which one is called as holy basil?
(a) Phyllanthus emblica
(b) Acalypha indica
(c) Ocimum sanctum
(d) Aegle marmelos
Answer:
(c) Ocimum sanctum

6. Marijuana is included under the family:
(a) Solanaceae
(b) Cannabiaceae
(c) Acanthaceae
(d) Euphorbiaceae
Answer:
(b) Cannabiaceae

7. Which of the following is used as Bio-pest repellent:
(a) Azadirachata indica
(b) Acalypha indica
(c) Vinca rosea
(d) Aegle marmelos
Answer:
(a) Azadirachata indica

8. Chenopodium quinoa is coming under:
(a) Pulses
(b) Cereals
(c) Nuts
(d) Pseudo-cereals
Answer:
(d) Pseudo-cereals

9. Choose the odd man out:
(a) Black gram
(b) Sorghum
(c) Pigeon gram
(d) Green gram
Answer:
(b) Sorghum

10. Choose the odd one:
(a) Coffea arabica
(b) Elettaria cardamomum
(c) Piper nigrum
(d) Cumcuma longa
Answer:
(a) Coffea arabica

11. Find out the odd one.
(a) Phyllanthin
(b) Azadictin
(c) Gibberillin
(d) Morphine
Answer:
(c) Gibberillin

12. Indicate the odd one.
(a) Nilavembu
(b) Garlic
(c) Indian gooseberry
(d) Vilvum
Answer:
(b) Garlic

13. Choose the correct one.

Answer:
(c)

14. Which of the following is not a correct pair?

Answer:
(d)

15. Which of the following is the correct pair?

Answer:
(b)

16. Choose the incorrect pair.

Answer:
(c)

17. Assertion: Phyllanthus is a well-known hepato protective plant used for the treatment of jaundice.
Reason: It has been scientifically proved that the extract of Pamarus is effective against hepatitis B virus.
(a) Both Assertion and Reason are correct, Assertion is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Assertion is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Assertion is correct, Reason is not correct.
(e) Both Assertion and Reason are not correct.
Answer:
(b) Both Assertion and Reason are correct, Assertion is not the correct explanation of Assertion.

18. Assertion: Medicinal plants play a significant role in providing healthcare services to urban people.
Reason: They serve as the therapeutic agents as well as important raw material for ’ the manufacture of traditional and modern medicines.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Assertion is correct, Reason is not correct.
(e) Both Assertion and Reason are not correct.
Answer:
(c) Assertion is not correct, Reason is correct.

19. Assertion: The essential oil from Jasmine is used in modern perfumery and cosmetics.
Reason: The aroma of Jasmine blends well with other perfumes.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Assertion is correct, Reason is not correct.
(e) Both Assertion and Reason are not correct.
Answer:
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.

20. Assertion: An orange dye “Henna” is obtained from the roots of Law Sonia inermis.
Reason: The principal colouring matter lacosone obtained from the root is harmless.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Assertion is correct, Reason is not correct.
(e) Both Assertion and Reason are not correct.
Answer:
(e) Both Assertion and Reason are not correct.

21. Which of the following statement is not correct?
(a) Traditionally turmeric is used as skin care cosmetics in Tamil Nadu.
(b) Aloe vera is an antioxidant.
(c) Perfumes are manufactured from essential oil.
(d) All the above statement are not correct.
Answer:
(d) All the above statement are not correct.

22. Choose the correct statement.
(a) Black pepper is known as the queen of spices.
(b) Cardamom is called as the king of spices.
(c) Black pepper is called as the ‘black gold of India’.
(d) None of the above.
Answer:
(c) Black pepper is called as the ‘black gold of India’.

23. Indicate the incorrect statement.
(a) The origin of red mango is Southern Asia
(b) The origin of red gram is Southern Irtdia.
(c) Lady’s finger is a native of Tropical Africa.
(d) Kodo millet is originated from Asia.
Answer:
(d) Kodo millet is originated from Asia.

24. Identify the correct statement.
(a) Rice is the chief source of carbohydrate.
(b) Wheat is the chief sources of protein.
(c) Edible oil is extracted from the husks of paddy.
(d) Rice bran is used as a fuel.
Answer:
(a) Rice is the chief source of carbohydrate.

Students get through the TN Board 12th Bio Botany Important Questions Chapter 9 Plant Breeding which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 9 Plant Breeding

Very short answer questions

Question 1.
Define organic farming.
Answer:
Organic fanning is defined as an alternative agriculture system, that sustains the health of soils, ecosystem and people, using natural inputs like organic manure, bio-pesticides etc.

Question 2.
Mention any two advantage of biofertilizers.
Answer:

1. Biofertilizers are eco-friendly organic agro-inputs.
2. They are more efficient and cost-effective than chemical fertilizers.

Question 3.
Name any two free-living nitrogen-fixing bacteria:
Answer:

1. Azotobactor
2. Clostridium

Question 4.
What is the importance of root nodule?
Answer:
The root nodules are the place, where the nitrogen-fixing symbiotic bacteria, Rhizobium resides and converts the atmospheric nitrogen into a bioavailable form to the plants.

Question 5.
Define Arbuscular Mycorrhizae.
Answer:
Arbuscular mycorrhizae (AM) is defined as the symbiotic association between certain phycomycetous fungi and angiosperm roots.

Question 6.
Explain Bio-pesticides.
Answer:
Bio-pesticides are biologically based agents j used for the control of plant pests.

Question 7.
Name any two green manure crops.
Answer:

1. Crotalaria juncea
2. Indigofera tinctoria

Question 8.
Define plant breeding.
Answer:
Plant breeding refers to the science of improvement of crop varieties with a higher yield, better quality, resistance to diseases and shorter duration for yield.

Question 9.
Define Mutagenesis.
Answer:
Mutagenesis is defined as the process by which developing new genetic diversity by exposing crop plants to chemical agents or radiation.

Question 10.
Explain hybridization.
Answer:
Hybridization refers to the method of producing new crop varieties, in which two or more plants of varying genetic constitution 1 are crossed to produce a hybrid.

Question 11.
Define Pseudoheterosis.
Answer:
Pseudoheterosis is defined as a hybrid I possessing superiority over parents in vegetative growth, but not in yield and adaptation, usually sterile or poorly fertile.

Question 12.
What are polyploids?
Answer:
Polyploids are plants that possess more than two sets of chromosomes.

Question 13.
Define green revolution.
Answer:
The green revolution is defined as the cumulative result of a series of research, development, innovation and technology transfer initiatives j in order to increase crop production.

Question 14.
Explain Biofortification.
Answer:
Biofortification is referred to as a process by which crops with high levels of vitamins and minerals or high protein and healthier fats are produced.

Question 15.
Mention any two methods of New Plant Breeding Techniques (NBT).
Answer:
The two methods of New Plants Breeding Techniques are:

1. Genetic Engineering
2. Plants tissue culture

Short answer questions

Question 1.
Explain organic agriculture.
Answer:
An alternative type of agriculture in which the agro-inputs are natural and ecofriendly is known as agro farming. It is originated early in the twentieth century. It is an agricultural production system that sustains the health of the soils, ecosystems and people. It relies on natural ecological processes, biodiversity and cycles adapted to local conditions rather than the use of inputs with adverse effect.

Question 2.
What are the characteristics of biofertilizers?
Answer:

1. The biofertilizers are the preparations of living cells or latent cells of microorganisms.
2. They should help the plants uptake of nutrients by their interactions. Eg: Mycorrhiza.
3. Biofertilizers are eco-friendly, cost-effective and more efficient than chemical fertilizers.

Question 3.
What are the advantages of Arbuscular mycorrhizae (AM)?
Answer:

1. Arbuscular mycorrhizae are the process of the symbiotic association between phycomycetous fungi and angiosperm roots.
2. They have the ability to mobilise the phosphate found in the soil abundantly.
3. They also provide the necessary strength to resist diseases, germs and unfavourable weather conditions.

Question 4.
Distinguish between Mass selection and Pureline selection.
Answer:

Mass selection	Pureline selection
Bulk of phenotypically similar plants are selected.	Single plant’s offsprings are selected.
They are heterogeneous cultivers.	Different purelines of cultivers are segregated.
They are registered and marketed.	They are homogenous cultivers.

Question 5.
Who coined the term mutation breeding? Write its advantages.
Answer:
The term “Mutation breeding” was coined by Muller and Stadler in 1927-28.
They have the advantage of improving the defect without losing an agronomic and quality character in agriculture and crop improvement. Gene mutations provide essential inputs for evolution as well as for recombination and selection. Seedless crops are developed by this method.

Question 6.
What are vegetables fortified with nutrients released by the Agricultural Research Institute?
Answer:

1. Vitamin A enriched carrot, spinach, pumpkin.
2. Vitamin C enriched bitter guard, bathua, mustard and tomato.
3. Iron and calcium-enriched spinach and bathura.
4. Protein-enriched beans, broad beans, lablab, French and garden peas.

Question 7.
List the plant’s resistance to insect pests developed through plant breeding.
Answer:

Crop	Variety	Insect pest
Brassica (Rapeseed mustard)	Pusa Gaurav	Aphids
Flat bean	Pusa sem2, pusa sem3	Jassids, aphids and fruit borer
Okra (Bhindi)	Pusasawani pusa A-4	Shoot and Fruit borer

Long answer questions

Question 1.
Write about polyploids breeding.
Answer:
Polyploids are plants, that possess more than two sets of chromosomes. Diploids (2n) number of chromosomes are present in the majority of flowering plants. Polyploids often exhibit increased hybrid vigour by increasing heterozygosity Polyploidy increase the tolerance to both biotic and abiotic stresses. It offers a buffering effect of deleterious mutations. The production of seedless varieties is possible due to meiotic error, Polyploidy often results in reduced fertility and is considered to be a major force in the evolution of both wild and cultivated plants.
Autopolyploidy and Allopolyploids are the two types of polyploids.
Autopolyploidy: The doubling of the chromosome by themselves in the same plant is called autopolyploidy.
Eg: Triploid condition in sugar beets, apple and pear. In tomato, it leads to seedless variety. Polyploidy can be induced by a chemical called colchicine.
Allopolyploids: The multiplication of chromosome sets that are initially derived from two different species, is called allopolyploidy.
Eg: Triticale (Triticum durum X Secale cereal), Raphanobrassica (Brassica oleraceae X Raphanus satious).

Question 2.
List out the objectives of plant breeding.
Answer:
The followings are the objectives of plant breeding.

1. The increase in crop yield, plant vigour and increase in the fertility of the plant are the main objectives of plant breeding.
2. Raise plants with increased tolerance to environmental factors like salinity, temperature and drought.
3. To prevent the premature falling of buds, fruits etc.
4. The synchronous maturity of gametes should be improved.
5. To develop plants that develop resistance to pathogens and pests.
6. To develop photosensitive and thermosensitive varieties of plants

Question 3.
What are the changes that take place in a plant species due to domestication?
Answer:

1. They have to adapt to a greater diversity of environments and a wider geographical range.
2. They may have simultaneous uniform flowering and Suiting.
3. Lack of shattering or scattering of seeds.
4. They may have increased the size of fruits and seeds.
5. They have to change from a perennial to an annual habit.
6. Change in the breeding system.
7. They may change to increased yield.
8. Increased resistance to disease and pest.
9. Parthenocarpic seedless fruits may be developed.
10. Enhancing colour, appearance palatability and nutritional composition.

Question 4.
Draw the diagram showing the benefits of Am colonization and label.
Answer:

Question 5.
Liquid seawater fertilizer is not only organic but also eco-friendly. Justify.
Answer:
Seaweed liquid fertilizer (SLF) contains organic nutrients, like cytokinin, gibberellins and auxin. It also contains macro and micronutrients. Seaweed liquid fertilizer is made from kelp (brown algae), which contains alginate. This alginate reacts with metals in the soil and forms long, cross-linked polymers, which improve the crumbling of soil, swell up when they get wet. It retains moisture for a long time. They are especially useful in organic gardening, which provides carbohydrate for plants.
This manure has more than 70 minerals, vitamins and enzymes which promote vigorous growth in plants. The plants grown in seaweed liquid fertilizer have improved resistance to frost and disease, indicating that this fertilizer is ecofriendly-pesticide.

Choose the correct answer.

1. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

2. Match the following (Vavilov’s centres):

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(d) (p)-(ii); (q)-(i); (r)-(iv);(s)-(iii)
Answer:
(c) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

3. Match the following:

(a) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(d) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
Answer:
(a) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)

4. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(a) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)

5. The method of creation of genetic variation includes:
(a) Mutation
(b) Hybridization
(c) Vegetative propagation
(d) Tissue culture
Answer:
(c) Vegetative propagation

6. Objective of plant breeding is:
(a) to increase yield
(b) to decrease tolerance to disease
(c) to increase sensitivity toi salinity
(d) to prevent synchronous maturity.
Answer:
(a) to increase yield

7. The introduction of foreign genes into DNA of a plant for the first time in the year:
(a) 1940
(b) 1985
(c) 1994
(d) 2000
Answer:
(c) 1994

8. Bacterial blight resistance was achieved in;
(a) Wheat
(b) Cowpea
(c) Chilli
(d) Cauliflower
Answer:
(b) Cowpea

9. Choose the odd man out.
(a) E.Borlaug
(b) M.S.Swaminathan
(c) Nel jayaraman
(d) N.G.P.Rao
Answer:
(c) Nel jayaraman

10. Find out the odd one out.
(a) Mutation
(b) Gene transfer
(c) Cytoplasmic fusion
(d) Polyploidy
Answer:
(c) Cytoplasmic fusion

11. Indicate the odd one out (Bio fortification)
(a) Protein content
(b) Fat content
(c) Vitamin content
(d) Gibberellin content
Answer:
(d) Gibberellin content

12. Choose the odd one out (NBT)
(a) Plant tissue culture
(b) Genetic Engineering
(c) Heterosis
(d) Somatic hybridization
Answer:
(c) Heterosis

13. Choose the correct pair.

Answer:
(a)

14. Choose the incorrect pair.

Answer:
(b)

15. Choose the correct pair.

Answer:
(b)

16. Choose the incorrect pair.

Answer:
(c)

17. Assertion: Organic agriculture is a production system that sustains the health of the soils, ecosystem and people.
Reason: Organic agriculture relies on ecological processes, biodiversity and cycles adapted to local conditions rather than the use of inputs with adverse effect.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct.
(d) Assertion is not correct, Reason is correct.
(e) Both Assertion and Reason are not correct.
Answer:
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.

18. Assertion: Biofertilizers are eco-friendly agro-inputs.
Reason: They are cost-effective and efficient than chemical fertilizers.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct.
(d) Assertion is not correct, Reason is correct
(e) Both Assertion and Reason are not correct.
Answer:
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.

19. Assertion: Rhizobium is best suited for paddy fields, which increase yield by 15-40%.
Reason: This nitrogen-fixing bacterium when applied in soil undergoes multiplication in billions and fix nitrogen into a usable form for plants.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct.
(d) Assertion is not correct, Reason is correct.
(e) Both Assertion and Reason are not correct.
Answer:
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.

20. Assertion: Trichoderma is symbiotic fungi, that are common in soil and root ecosystem.
Reason: They have been recognized as bio-control agent for plant disease.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct.
(d) Assertion is not correct, Reason is correct.
(e) Both Assertion and Reason are not correct.
Answer:
(c) Assertion is correct, Reason is not correct.

21. Which of the following statement is correct?
(a) Most important green manure crops are Vinca rosea, Crotalaria and Thespecia.
(b) Most important green manure crops are Indigotera, Abitelon and Banian tree.
(c) Most important green manure crops are Crotalaria juncea, Tephrosia purpurea, and Indigofera tinctoria.
(d) None of the above.
Answer:
(c) Most important green manure crops are Crotalaria juncea, Tephrosia purpurea, and Indigofera tinctoria.

22. Choose the incorrect statement.
(a) The aim of plant breeding is to increase yield.
(b) The aim of plant breeding is to increase the fertility of crop.
(c) The aim of plant breeding is to increase tolerance to environmental conditions.
(d) All the above statements are not correct.
Answer:
(d) All the above statements are not correct.

23. Find out the correct statement.
(a) William S. Gaud coined the term mutation breeding.
(b) Muller and Stadler coined the term green revolution.
(c) M.S.Swaminathan is a pioneer mutation breeder.
(d) Nel Jayaraman hails from Andhra Pradesh.
Answer:
(c) M.S.Swaminathan is a pioneer mutation breeder.

24. Indicate the incorrect statement.
(a) Wheat variety Atlas 66 have high protein content.
(b) Wheat variety Atlas 66 have less protein content.
(c) Wheat variety Atlas 66 have been used as a donor for improving cultivated wheat.
(d) None of the above.
Answer:
(b) Wheat variety Atlas 66 have less protein content.

Students get through the TN Board 12th Bio Botany Important Questions Chapter 8 Environmental Issues which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 8 Environmental Issues

Very short answer questions

Question 1.
Define the greenhouse effect.
Answer:
The greenhouse effect is defined as a process by which the radiant heat from the sun is captured by gases in the atmosphere, leading to an increase in atmospheric temperature.

Question 2.
Define global warming.
Answer:
Global warming is a process through which the mean global temperature increases due to the increased concentration of greenhouse gases.

Question 3.
Mention any two natural sources of methane in the atmosphere.
Answer:

1. Paddy fields
2. Bacterial action in water bodies.

Question 4.
Expand CDM.
Answer:
CDM means Clean Development Mechanism.

Question 5.
Mention any two plants which can indicate SO2 pollution.
Answer:

1. Ficus
2. Pinus

Question 6.
What do you mean by social forestry?
Answer:
Social forestry refers to the management of forest and afforestation on barren lands with the purpose of helping the environmental, social, and rural development and benefits.

Question 7.
Mention any two causes of Deforestation.
Answer:

1. Agriculture plantation and livestock ranching are one of the main causes of deforestation.
2. Disproportionate felling of trees for timber.

Question 8.
Define Alien species.
Answer:
Alien species is defined as a non-native species to the ecosystem on the country, which poses a serious threat to the native species and ecosystem.

Question 9.
Name any two invasive plant species in India.
Answer:
The invasive plant species are:

1. Prosopis juliflora
2. Eichhornia crassipes.

Question 10.
Define Endemic species.
Answer:
Endemic species are defined as plants or animals that exist only in one geographic region.

Question 11.
Define carbon sequestration.
Answer:
Carbon sequestration is defined as a process through which capturing and storing of carbon-di-oxide in the atmosphere take place.

Question 12.
What is Biochar?
Answer:
Biochar is a long-term method to increase the ability of plants to store more carbon.

Question 13.
Expand EIA.
Answer:
EIA means Environmental Impact Assessment.

Short answer questions

Question 1.
Explain briefly about remote sensing.
Answer:
Remote sensing is the acquisition of information about an object without making physical contact with the object by measuring its reflected and emitted radiation at a distance from the target area. It gives exact pictures and data on the identification of even a single tree in a large area of vegetation and wildlife. It is also helpful in the identification of biodiversity-rich or fewer areas for futuristic works on conservation and restoration of biota. It helps in the maintenances of various species including commercial crops, medicinal plants, and threatened plants.

Question 2.
What is biomonitoring? Explain it briefly.
Answer:
Biomonitoring is the act of observing and assessing the current state and changes in the ecosystem, biodiversity components, landscape including natural habitat, population, and species. Eg: In an agricultural drone, a bird’s eye view of a farmer can reveal many issues like irrigation problems, soil variation, and pests as well as fungal infestation. It is used in farming in order to help increased crop production and monitor crop growth. It is also helpful for a cost-effective safe methods of spraying pesticides and fertilizer.

Question 3.
Invasion of alien species disrupts ecosystem processes. Justify.
Answer:
The alien species disrupt ecosystem processes, because

1. They threaten biodiversity, reduce native herbs, reducing ecosystem services (benefits).
2. They only alter the ecosystem and micro intimate by prolific spreading.
3. They also alter the nature of the soil and make it unsuitable for native species.
4. They create human health problems like allergies.
5. Thus they degrade the local environment and eliminate important local species.

Question 4.
Mention any three achievements of the Afforestation project.
Answer:

1. Degraded forests were restored.
2. Environmental and ecological stability was maintained.
3. Afforestation was helpful to conserve bio-diversity, wildlife, and genetic resources.

Question 5.
Distinguish between Agroforestry and social forestry.
Answer:

Agroforestry	Social forestry
Agroforestry is an integration of trees crops and livestock on the same piece of land.	Social forestry refers to the management of forests and afforestation on barren lands.
Main objective of this is to build interaction among above components.	Main objective includes helping environmental, social and rural development and their benefits.
Intercropping of two or more crops between different species of trees and shrubs resulting in higher yield and reduction in operation cost.	Social forestry programme is carried out for the benefit of people and participation of people in order to reduce pressure on forest.

Question 6.
Mention any three major activities of forestry extension centers.
Answer:

1. Imparting training to the public on tree growing methods.
2. Publicity and propaganda of the advantage of tree growing,
3. Raising the seedlings of important tree species and supply to the public with subsidies.

Question 7.
Write down any three effects of- global warming on plants.
Answer:

1. Global warming leads to low agricultural productivity.
2. Weeds, pests, and fungi which need warmer temperature, will increase in number due to global warming.
3. Global warming may change the flowering seasons and pollinators.

Question 8.
Mention any three causes of greenhouse gas emission.
Answer:

1. Agriculture practices and animal husbandry practices lead to the emission of CH₄.
2. CO₂ and CH₄, are produced by burning fossil fuels.
3. The household items like electrical gadgets including refrigerators and air conditioners release chlorofluorocarbon.

Long answer questions

Question 1.
List the objectives of Afforestation:
Answer:

1. One of the prime objectives of Afforestation is to increase forest cover by planting more trees, which increases O₂ production and air quality.
2. Rehabilitation of degraded forests to increase CO₂ fixation, leading to reduction of atmospheric carbon dioxide.
3. Medicinal plants are planted in mixed plantations and produce natural medicines.
4. Regeneration of indigenous herbs and shrubs.
5. The other objectives include the increase of availability of water table or groundwater, reduction of nitrogen leaching from the soil, and reduction of nitrogen contamination of drinking water.

Question 2.
List the plants used as plant indicators of pollutions.
Answer:

Plants	Indicator for pollutants
Ficus, Lichens, Pinus, and Rose.	SO2 Pollution.
Petunia and Chrysanthemum	Nitrate contamination.
Gladiolus	Fluoride pollution.
Robinia pseudo­acacia (Black locust tree)	Indicator of heavy metal contamination.

Question 3.
Distinguish between in-situ and ex-situ conservation.
Answer:

In-situ Conservation	Ex-situ conservation
In insitu conservation, the conservation of management of genetic resources in their natural habitats	In ex-situ conservation the species are protected outside their natural environment.
In this method, forest trees, medicinal and aromatic plants under thread are conserved within the existing habitat.	The plants are conserved is botanical gardens, and following some of conservation strategies like gene, pollen, seed in-vitro conservation cryo preservation, seedling, tissue culture and DNA banks.

Question 4.
Write about Biodiversity impact Assessment. How will you assess the impact?
Answer:
Biodiversity Impact Assessment (BIA) can be defined as a decision-supporting tool to help the development considering bio-diversity as an inclusive component followed by planning and implementation.
It integrates biodiversity consideration for developmental proposals.
They are legally bound mechanisms for implementing the conservation of biodiversity resources. They also provide fair and equitable sharing of the benefits arising from the use of bio-diversity.
The Bio-diversity impacts can be assessed by:

1. Change in land use and cover.
2. Fragmentation and isolation.
3. Extraction.
4. External inputs such as emissions, effluents, and chemicals.
5. Introduction of invasive, alien, or genetically modified species.
6. Impact on endemic and threatened flora and fauna.

Question 5.
List the importance of GIS.
Answer:

1. GIS is used in Environmental Impact Assessment.
2. It is also helpful in disaster management.
3. It is used in the zoning of landslide hazards.
4. It helps in the determination of land cover and land use.
5. It is used to determine flood damage.
6. It is used in the management of natural resources.
7. Soil mapping and wetland mapping can be done using GIS.
8. Identification of volcanic hazards and irrigation management can be carried out by this information.
9. It helps to study vegetation and to map threatened and endangered species.

Activity

Students may form ‘ECOGROUPS’ and discuss eco-issues of their premises and find solutions to the existing problems like litter disposal, water stagnation, health, and hygiene, greening the campus, and its maintenance.
Eco groups discussion topics:

1. Litter disposal: The litter forms solid waste which includes degradable and non-degradable waste. The degradable waste can be degraded to manure using bacteria and earthworms. Non- degradable waste like plastic can be recycled.
2. Water stagnation: Solution: Setting up of water harvesting system will solve water stagnation.
3. Health and hygiene: Solution: Keep the surroundings clean and neat. Follow personal hygiene strictly. Create awareness among the public.
4. Greening the campus: Solution: A tree planting programme may be initiated in the campus. Each member of Eco groups may be given responsibility for maintaining one or two trees in the campus.

Multiple choice questions

1. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

2. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(c) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)

3. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
Answer:
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)

4. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

5. Choose the odd man out.
(a) Sudhir kumar Sopary.
(b) Jadav molai Payeng
(c) Panduranga Hegde
(d) Swaminathan
Answer:
(d) Swaminathan

6. Find out the odd one.
(a) Western ghat
(b) National park
(c) Gulf of mannar
(d) Agasthiar malai
Answer:
(c) Gulf of mannar

7. Indicate the odd one (Ex-situ conservation)
(a) Pollen
(b) Seed
(c) Seedling
(d) Leaf
Answer:
(d) Leaf

8. Choose the odd one:
(a) Carbon-di-oxide
(b) Ammonia
(c) Methane
(d) Nitrous oxide
Answer:
(b) Ammonia

9. Choose the incorrect pair.

Answer:
(c)

10. Choose the incorrect pair?

Answer:
(d)

11. Which of the following is a correct pair?

Answer:
(a)

12. Choose the incorrect pair:

Answer:
(c)

13. Find out the plant indicator. depletion.
(a) Water Lilly
(b) Coconut
(c) Acacia sp
(d) Gladiolus
Answer:
(d) Gladiolus

14. Ozone depletion in the atmosphere results in:
(a) UV radiation
(b) CO₂ emission
(c) Nitrogen depletion
(d) Afforestation
Answer:
(a) UV radiation

15. Which of the following is a hedge plant.
(a) Azadirachta indica
(b) Acacia spp
(c) Teak
(d) Eucalyptus
Answer:
(b) Acacia spp

16. Alien invasive species include.
(a) Casuarina
(b) Amelia dubia correct.
(c) Prosopis juliflora
(d) Bamboo
Answer:
(c) Prosopis juliflora

17. Assertion: Majority of endemic species are threatened.
Reason: Because of their narrow specific habitat, reduced seed production low dispersal rate, less viable nature and human interference.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct.
(d) Both Assertion and Reason are not correct.
(e) Assertion is not correct, Reason is correct.
Answer:
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.

18. Assertion: Eichhornia crassipes increases the oxygen content of water bodies.
Reason: Anoxic condition in water bodies leads to Eutrophication.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct.
(d) Both Assertion and Reason are not correct.
(e) Assertion is not correct, Reason is correct.
Answer:
(e) Assertion is not correct, Reason is correct.

19. Assertion: In plants, photosynthetic chemicals will be affected due to ozone depletion.
Reason: Decreased photosynthesis will result in increased atmospheric CO₂, resulting in global warming.
(a) Both Assertion and R are correct, R is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct.
(d) Both Assertion, and Reason are not correct.
(e) Assertion is not correct, Reason is correct.
Answer:
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.

20. Assertion: In Agroforestry, nutrient cycling between species improves and organic matter in the soil is maintained.
Reason: Because of the absence, of microorganisms, insects, and earthworm in the soil.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are Correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct
(d) Both Assertion and Reason are not correct.
(e) Assertion is not correct, Reason is correct.
Answer:
(c) Assertion is correct, Reason is not correct

21. Which of the following statement is correct?
(a) Trees provide microclimate for crops.
(b) They disturb O₂-CO₂ balance.
(c) Trees increase atmospheric CO₂.
(d) Trees cause decrease in relative humidity in atmosphere.
Answer:
(a) Trees provide microclimate for crops.

22. Choose the incorrect statement.
(a) Ozone depletion increases the incidence of cataract in human.
(b) It also causes lung irritation.
(c) Ozone depletion enhances the functioning of immune system.
(d) It increases the incidence of mutation:
Answer:
(c) Ozone depletion enhances the functioning of immune system.

23. Find out the correct statement.
(a) Prosophis juliflora is a native species found in Tamil Nadu.
(b) It is an aggressive coloniser.
(c) It is an invasive species native of South Africa.
(d) None of the above.
Answer:
(b) It is an aggressive coloniser.

24. Indicate the incorrect statement.
(a) Hardwickia binata is an endemic tree.
(b) It is endemic to peninsular and northern India.
(c) It is endemic to Kerala and Tamil Nadu.
(d) None of above.
Answer:
(c) It is endemic to Kerala and Tamil Nadu.

Students get through the TN Board 12th Bio Botany Important Questions Chapter 7 Ecosystem which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 7 Ecosystem

Very short answer questions

Question 1.
Define ecosystem.
Answer:
The ecosystem is defined as the structural and functional unit of ecology.

Question 2.
Mention the major components of the ecosystem.
Answer:

1. Abiotic components – Nonliving
2. Biotic components – Living

Question 3.
What is Photosynthetically Active Radiance (PAR)?
Answer:
Photosynthetically Active Radiation is the amount of light available for the photosynthesis of plants.
This is the range between 400-700 nm wavelength.

Question 4.
Give any two functions of the ecosystem.
Answer:

1. Energy cycling
2. Cycling of materials between the living and non-living components.

Question 5.
Define productivity.
Answer:
Productivity is defined as the rate of biomass production per unit area in a unit of time.

Question 6.
Define community productivity.
Answer:
Community productivity is defined as the rate of net synthesis of organic matter by a group of plants per unit area in a unit of time.

Question 7.
What is meant by the food web?
Answer:
Food web is a web like arrangement in which the interlocking pattern of a number of food chain exist.

Question 8.
Define ecological pyramid.
Answer:
An ecological pyramid is defined as the graphic representation of trophic structure and function at successive trophic levels of an ecosystem.

Question 9.
Explain Humification.
Answer:
Humification is a process by which the dark-colored amorphous substance (humus) is formed from simplified detritus.

Question 10.
Mention the types of freshwater ecosystems.
Answer:

1. Lotic – running water bodies.
2. Lentic – Standing water bodies.

Question 11.
Mention any two phytoplankton in the pond ecosystem.
Answer:

1. Oscillatoria
2. Anabaena

Question 12.
The photosynthesis is more in a limnetic zone of the pond. Why?
Answer:
The photosynthesis is more in the limnetic zone of a pond, because of the greater penetration of i sunlight.

Question 13.
Mention any two cultural services of the ecosystem.
Answer:

1. Education and inspiration.
2. Spiritual and religious values.

Question 14.
List out two factors, which affect the ecosystem.
Answer:

1. Deforestation and over-grazing.
2. Habitat destruction.

Question 15.
What is ecosystem resilience?
Answer:
Ecosystem resilience is the ability of the ecosystem to resist damage caused by disturbances from flood, fire, infection, predation drought, etc., and recover quickly.

Short answer questions

Question 1.
Explain briefly about autotrophic succession.
Answer:
Autotrophic succession is the condition, in which the green plants are dominant during the early stage of succession. If the soil is rich in inorganic substances, this succession occurs. As the green plants dominate at the beginning of this succession, an increase in organic matter in the ecosystem results. The energy flow subsequently increases in the ecosystem.

Question 2.
Describe the different levels of consumers in the pond ecosystem.
Answer:
In the pond ecosystem, the primary consumers include zooplanktons like Paramoecium, Daphnia, etc., The bottom-dwelling benthic organisms include mollusks and annelids. The water beetle and frogs form the secondary consumers. Ducks and cranes constitute the tertiary consumers (carnivores). Large fish, hawk man, etc., are the top carnivores in the pond ecosystem.

Question 3.
Distinguish between lotic and lentic ecosystems.
Answer:

Lotic Ecosystem	Lentic Ecosystem
It is running water ecosystem.	It is standing water body.
It includes river spring and stream.	It includes ponds and lakes.
In times of drought shallow systems will dry up and many organism will die.	During periods of drought these systems will often last longer than its counterpart.

Question 4.
Explain ten percent law.
Answer:
Lindeman in 1942 proposed a ten percent law. This law states that when the energy is transferred from one trophic level to another trophic level, only 10% of food energy is stored at every level. The rest of food energy (90%) is lost through respiration, decomposition, and in the form of heat. Hence this law is called the ten percent law.

Question 5.
Distinguish between macro consumers and micro consumers.
Answer:

Macro consumers	Micro consumers
Macro consumers refer to herbivores, carnivores, omnivores.	Micro consumer are decomposers.
They are primary secondary and tertiary consumers	Organisms that decompose dead plants and animals to release organic and inorganic nutrients, which are reused by plants.
Eg: Rabbit, hawk, lion etc.	Eg: Bacteria, Actinomycetes, Fungi etc.

Question 6.
Write a diagrammatic representation of energy flow.
Answer:

Question 7.
Write down the significance of the food web.
Answer:

1. The Food web is made to explain species interaction (Direct interaction).
2. It is also helpful to illustrate indirect interaction among different species.
3. It can be used to study the community structure of an ecosystem.
4. Food web can be used to reveal different patterns of energy flow in terrestrial and aquatic ecosystems.

Long answer questions

Question 1.
Write in detail about the concept of trophic level in an ecosystem.
Answer:
The position of an organism in a food chain is referred as a trophic level. The number of steps in a food chair is equal to the number of trophic levels in an ecosystem.
The first trophic level (T₁) is occupied by green plants and they are called producers.
The primary consumers are in the second trophic level (T₂) and they utilize the energy produced by the producers. They are called herbivores. The herbivores are eaten by carnivores and they occupy the third trophic level (T₃). They are also called secondary consumers or primary carnivores. The fourth trophic level (T₄) is occupied by carnivores which eat on primary carnivores. They are otherwise known as tertiary consumers or secondary carnivores. The omnivores eat ‘ both plants and animals. They may occupy more than one trophic level in the food chain.

Question 2.
Explain food web with suitable diagram.
Answer:
Food web is a web like arrangement in which the interlocking pattern of a number of food chain can exist. It is the basic unit of an ecosystem, to maintain its stability in nature. It is otherwise known as homeostasis.
Eg: In a grazing food chain of a grass land, a mouse may also eat food grains in the absence of rabbit in the ecosystem. The mouse in turn may be eaten directly by a hawk or by a snake and a snake may directly be eaten by hawk.
Therefore, the interlocking pattern of the food chain is the food web. The species of an ecosystem may remain balanced to. each other by some sort of natural check.

Question 3.
Draw the diagrammatic representation of pyramids of biomass in different types of ecosystems.
Answer:

Question 4.
How do anthropogenic activities affect ecosystem services?
Answer:
Human being and their activities make the destruction of the ecosystem. We all exploit nature than that of our needs. The ecosystem is exploited in order to meet rapidly growing demands for food, freshwater, medicine, timber, fiber and fuel. The deterioration, caused by present-day human activities changed the ecosystem rapidly and extensively than in any comparable period of time in human history.
The followings are factors caused by human activities which disturb an ecosystem.

1. The destruction of habitats.
2. Deforestation and over-grazing.
3. Erosion of soils.
4. Introduction of alien species.
5. Overharvesting of plant material.
6. Pollution of land, water, and air.
7. Runoff pesticides, fertilizers, and animal waste.

Question 5.
Write down the strategies of ecosystem management.
Answer:
The strategies of ecosystem management are as follows.

1. The biodiversity of ecosystems ought to be maintained.
2. Flagship species are the species that indicate the health of the ecosystem. This helps in indicating the damaged ecosystem.
3. It is helpful to recognize the inc it Vilify of ecosystem change and plans accordingly.
4. The sustainability of the ecosystem through sustainable development can be achieved by a strategy of ecosystem management.
5. The ecosystems, which are in need of rehabilitation can be identified by this strategy.
6. The management strategy involves government agencies, the local population, communities, and NGOs.
7. To build the capacity of local institutions and communities in order to create responsibility for the long-term implementation of ecosystem management activities.

Choose the correct answers.

1. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(ii)
Answer:
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)

2. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(u); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
Answer:
(a) (p)-(iv); (q)-(iii); (r)-(u); (s)-(i)

3. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

4. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(d) (p)-(iii); (q)-(i): (r)-(iv); (s)-(ii)
Answer:
(d) (p)-(iii); (q)-(i): (r)-(iv); (s)-(ii)

5. Match the following.

(a) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(a) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)

6. Which of the following is not a biotic factor?
(a) Bacteria
(b) Fungi
(c) Carbohydrate
(d) Algai
Answer:
(c) Carbohydrate

7. Which of the following is an omnivore?
(a) Eagle
(b) Crow
(c) Rabbit
(d) Hawk
Answer:
(b) Crow

8. The movement of decomposed water-soluble organic and inorganic compounds from the surface to the lower layer of soil is called:
(a) Eluvation
(b) Filtration
(c) Sublimation
(d) Diffusion
Answer:
(a) Eluvation

9. Gaseous cycle in the atmosphere includes:
(a) Ammonia, oxygen and methane cycle
(b) Oxygen, nitrogen and ammonia cycle
(c) Oxygen, carbon, and nitrogen cycle
(d) Carbon dioxide, nitrogen, and methane cycle
Answer:
(c) Oxygen, carbon, and nitrogen cycle

10. Identify the regulating service of the ecosystem:
(a) Nutrient cycle
(b) Erosion
(c) Education value
(d) Medicines
Answer:
(b) Erosion

11. Choose the odd man out:
(a) Vernadsky
(b) Karl Mobius
(c) Watson
(d) Friederichs
Answer:
(c) Watson

12. Find out the odd one out:
(a) Mouse
(b) Deer
(c) Elephant
(d) Tiger
Answer:
(d) Tiger

13. Indicate the odd one out:
(a) Fragmentation
(b) Infiltration
(c) Catabolism
(d) Humification
Answer:
(b) Infiltration

14. Choose the odd one out:
(a) Forest
(b) Pond
(c) Maize field
(d) Lentic
Answer:
(c) Maize field

15. Identify the odd one out:
(a) Water cycling
(b) Seed dispersal
(c) Pest regulation
(d) Water purification
Answer:
(a) Water cycling

16. Which of the following is a correct pair?

Answer:
(c)

17. Find out the incorrect pair.

Answer:
(c)

18. Choose the correct pair.

Answer:
(b)

19. Identify the incorrect pair.

Answer:
(d)

20. Which of the following is the correct pair?


Answer:
(c)

21. Assertion: |n m0st ecosystems, green plants are autotrophs.
Reason: They have chlorophyll, which enables them to produce carbo-hydrate from simple inorganic components.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false. The reason is true.
(d) Assertion and Reason are false.
Answer:
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.

22. Assertion: The product of starch is formed during photosynthesis by the combination of reactants such as chlorophyll, H₂O and carbon dioxide.
Reason: The energy stored in starch is obtained from the external source (light energy from sun)
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is true.
(d) Assertion and Reason are false.
Answer:
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.

23. Assertion: In a forest ecosystem, the pyramid of numbers is somewhat different in shape.
Reason: The pyramid of numbers in the forest ecosystem looks spindle-shaped.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is hot the correct explanation of Assertion.
(c) Assertion is false, Reason is true.
(d) Assertion and Reason are false.
Answer:
(b) Assertion and Reason are correct, Reason is hot the correct explanation of Assertion.

24. Assertion: Seagrasses and mangroves of Estuarine and coastal ecosystems are called as blue carbon ecosystems.
Reason: They are more efficient in carbon sequestration.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is true.
(d) Assertion and Reason are false.
Answer:
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.

25. Assertion: By 2025, at least 90% of the world’s population is projected to face water scarcity.
Reason: By 2025, 70% of forest cover will be destroyed.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is true.
(d) Assertion and Reason are false.
Answer:
(d) Assertion and Reason are false.

26. Which of the following statement is correct?
(a) Cultural services of the ecosystem include Ecotourism.
(b) Cultural services of the ecosystem include water purification.
(c) Cultural services of the ecosystem include water cycling.
(d) None of the above.
Answer:
(a) Cultural services of the ecosystem include Ecotourism.

27. Choose the incorrect statement:
(a) Mangrove ecosystem offers habitat for aquatic plants and animals.
(b) Mangrove ecosystem acts as a nursery for aquatic animals.
(c) It helps salt spray from waves.
(d) It provides medicine, fuelwood, and timber.
Answer:
(c) It helps salt spray from waves.

28. Find out the correct statement.
(a) The pyramid of energy is always spindle-shaped.
(b) The Pyramid of energy is always upright
(c) The pyramid of numbers in the forest ecosystems is always inverted.
(d) None of the above.
Answer:
(b) The Pyramid of energy is always upright

29. Indicate the incorrect statement.
(a) Ten-point law was proposed by Lindeman.
(b) The concept of ecological pyramids was introduced by Charles Elton.
(c) The ecosystem was defined by Odum
(d) All the above statements are not correct.
Answer:
(d) All the above statements are not correct.

30. Indicate the correct statement.
(a) All the primary producers are autotrophs.
(b) All the consumer are carnivores
(c) All the herbivores are only grass eaters.
(d) None of the above.
Answer:
(a) All the primary producers are autotrophs.

Students get through the TN Board 12th Bio Botany Important Questions Chapter 6 Principles of Ecology which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 6 Principles of Ecology

Very short answer questions

Question 1.
What is paleoclimatology?
Answer:
Paleoclimatology is a branch of climatology, which helps to reconstruct past climates of our planet and flora, fauna, and ecosystem in which they lived.
Eg: Air bubbles trapped in ice for tens of thousands of years with fossilized pollen, coral, plant, and animal debris.

Question 2.
What is meant by Heliophytes? Give example.
Answer:
Heliophytes are light-loving plants. Eg: Angiosperm.

Question 3.
What is Timberline?
Answer:
Timberline or tree line is an imaginary line in a mountain or higher areas of land, beyond which trees do not grow. This limit is calculated to be about 3000 to 4000m.

Question 4.
Name the gases present in the atmosphere.
Answer:

1. Nitrogen – 78%
2. Oxygen – 21%
3. Carbon dioxide – 0.03%
4. Argon and other gases – 0.93%

Question 5.
Name any two plants that used for phytoremediation of cadmium.
Answer:

1. Rice
2. Eichhomia

Question 6.
What is pyrophilous fungi? Give an example.
Answer:
Pyrophilous fungi are the fungi that grow in the soil of burnt areas after the fire.
Eg: Pyroriema confluence.

Question 7.
Explain briefly about the Edaphic factor.
Answer:
Edaphic factors are abiotic factors of soil.
It includes the composition of the soil in an area, including the physical and chemical composition of the soil.

Question 8.
What are soil organisms?
Answer:
The soil organisms are the living organisms, which live in the soil.
Eg: Bacteria, fungi, algae, protozoans, nematodes, insects, earthworms, etc.

Question 9.
Define cryptophytes.
Answer:
Cryptophytes are the plants that live below the surface of the soil.

Question 10.
Define Edge effect.
Answer:
Edge effect is defined as the phenomenon in which an organism or species are seen in ecotone areas due to the effect of an environment of two habitats.
Eg: Owl present between the forest and grassland area.

Question 11.
Name any two nitrogen-fixing bacteria.
Answer:

1. Anabaena
2. Nostoc

Question 12.
What is the negative interaction of species?
Answer:
In negative interaction of species, one species is benefited and the other is harmed.

Question 13.
Mention any two plants, which show defensive mechanisms against their predators.
Answer:

1. Tobacco produces nicotine
2. Opuntia has spines.

Question 14.
Define Amensalism.
Answer:
Amensalism is the phenomenon of the interaction of two species, in which one is inhibited by the secretion of certain chemical substances. The other species is neither harmed nor benefited.

Question 15.
Name any two amphibious plants.
Answer:

1. Typha
2. Sagittaria

Question 16.
Mention any two root morphological adaptations in hydrophytes.
Answer:

1. Roots are totally absent in Wolffia and Salvinia.
2. The root pockets replace root caps. Eg: Eichhornia.

Question 17.
Mention any two stem modifications in xerophytes for example.
Answer:

1. Cladode in Asparagus
2. Phylloclades in Opuntia

Question 18.
What are Tropophytes?
Answer:
Tropophytes are plants that act as xerophytes during summer and act as mesophytes or hydrophytes during the rainy season.

Question 19.
Define Autochory. Give example.
Answer:
Autochory is a process through which seed disperse takes place by a sudden burst of fruit with a force enabling to throw the seeds little away from the parent plant.
Eg: Impatients, crossandra.

Question 20.
Explain briefly about pneumatophores.
Answer:
Pneumatophores are special types of roots present in halophytes. They are negatively geotropic and respiratory in function.
Eg: Avicennia.

Short answer questions

Question 1.
Distinguish between Autecology and synecology.
Answer:

Autecology	Synecology
Autecology is the ecology of an individual species.	Synecology is the ecology of population or community.
It is also called as species ecology.	It is also called as community ecology.

Question 2.
Explain commensalism with a suitable example.
Answer:
Commensalism is an interaction between two organisms. In this type, one organism is benefited, while the other is neither harmed nor benefited. The organism, that is benefited is called the commensal, and other organisms are the host.
Eg: The plants like Vanda, growing on other plants without harming the host. These plants are called epiphytes and are commonly seen in the tropical rain forest.

Question 3.
Give examples of tolerance to cadmium toxicity in the soil.
Answer:

1. Plants like soybean and tomato can tolerate high concentrations of cadmium in the soil. They isolate cadmium and storing into few groups of cells. This in turn prevents the cadmium from affecting other cells.
2. Plants like rice and Eichhomia can tolerate cadmium but binding it to their proteins.
   These plants can be used to remove cadmium from contaminated soil.

Question 4.
Vegetation at different altitudes varies, showing distinct zonation why?
Answer:
Vegetation at different altitudes varies because of the following reasons:

1. The velocity of wind remains high at high altitudes.
2. The atmospheric temperature and air pressure decrease with an increase in height in high altitudes.
3. The timidness and intensity of light increase at high altitudes.

Question 5.
Name any three plants which show a defense mechanism against predators. Mention their mechanisms.
Answer:

1. Cinchona – Produces a chemical compound, quinine.
2. Bougainvilla – has thorns that produce it from animals.
3. Cacti – Produces latex, which protects them from predators.

Question 6.
Give any three examples of Amensalism.
Answer:

1. Penicillin produced by Penicillium notation inhibits the dying growth of a variety of bacteria, especially Staphylococcus.
2. The growth of fungus, Aspergillus is inhibited by Trichoderma.
3. An alkaloid, the jungle is secreted by roots and hulls of black walnut, Juglans nigra, inhibits the growth of seedlings of apple, tomato, and Alfalfa around it.

Question 7.
Name any three plants, which are called rooted submerged hydrophytes.
Answer:

1. Vallisneria
2. Hydrilla and
3. Isoetes.

Question 8.
What are the stem adaptations in hydrophytes?
Answer:
In hydrophytes the stem is adapted to suit the aquatic mode of life as follows:

1. In submerged plants, the stem is long, slender, spongy, and flexible.
2. In free-floating plants, a thick, short, stoloniferous, and spongy stem is present while in rooted floating forms, the stem is modified as a rhizome.
3. The vegetative propagation is also done through stem cuttings and their modifications like a rhizome, runners, etc.

Question 9.
What are the different types of xerophytic habitat? Explain them.
Answer:
There are two types of xerophytic habitats namely physical and physiological.

1. Physical dryness: In these habitats, the soil has a little amount of water due to low rainfall and the inability of the soil to retain water.
2. Physiological dryness: In this habitat, the plants are unable to absorb water, because of the absence of capillary spaces, even though sufficient water is available.
   Eg: Plants in salty and acidic soil.

Question 10.
Mention any three adaptations in the seeds and fruits of hydrochory plants.
Answer:
The plants which grow in or near water bodies, disperse their seeds, fruits through the water. They have certain adaptations for the dispersal of seeds and .fruits and they are:

1. The fruits of some plants like, Nelumbo have open coel receptacle with prominent air Space for floating.
2. In plants like coconut, the presence of fibrous mesocarp and light percap aids the fruits to float in water.
3. In plants like Heritiera littoralis, the fruits may be inflated, so that it can float in water.

Long answer questions

Question 1.
What is Autochory? Give an account of adaptations in fruits of autochory plants.
Answer:
Autochory is one of the types of seed dispersal, through which the seeds are dispersed by a sudden burst of fruits with a force. Autochory shows the following adaptations.

1. In some plants, the ripened fruits explode suddenly and seeds are dispersed with of great force by the mere touch of the plant. Eg: Inpatient (Balsam), Hura
2. In some plants, the fruits burst with noise and scatter the seeds, when they come in contact with water due to a shower of rain. Eg: Ruellia and Crassandia.
3. Some long pods explode with a loud noise like a cracker, dispersing the seeds in all directions. Eg: Bauhinia viable.
4. In some fruits, the dispersal of seeds takes place due to a high turgor pressure developed inside the fruit, when tissues around seeds are converted into a mucilaginous fluid. Eg: Ecballium elaterium, Gyrocarpus, and Dipterocarpus.

Question 2.
List out the anatomical adaptions of epiphytic plants. Draw and label the T.S section of the aerial root of an orchid.
Answer:

1. The roots of these plants have multilayered epidermis. The Exodermis layer is present inner velamen tissue.
2. The transpiration is reduced due to the presence of thick cuticle and sunken stomata.
3. Well-developed parenchymatous cells to store water is present in succulent epiphytes.
   

Question 3.
Give an account of an Example of Mutualism in the plant kingdom.
Answer:
Mutualism is an interaction between two species in which both species are benefited from obligate association. The common examples of mutualism are as follows.

1. The bacteria, Rhizobium lives in the nodules of leguminous plants, establishing a symbiotic association. The bacteria fix atmospheric nitrogen into nitrate for the leguminous plant, which in turn supplies food to the bacteria.
2. The association of water fem (Azolla) and nitrogen-fixing cyanobacterium (Anabaena) is a mutualism, in which the bacteria harbors in the water fem will fix atmospheric nitrogen for the Azolla.
3. The nitrogen-fixing Anabaena is present in coralloid roots of cycas (Gymnosperm) fixes atmospheric nitrogen into nitrate, making it available for the host cycas. The cycas provide food for the bacteria.
4. The association of cyanobacterium (Nostoc) found in the thalloid body of. Bryophyte (Anthoceros) is a mutual association. In this, the bacteria fix atmospheric nitrogen and the Bryophyte into supplies shelter and food to the cyanobacterium.
5. Other mutual associations are:
   (a) Wasps present in fruits of fig.
   (b) The association of algae and a fungus is the Lichen.
   Micorrhiza is the mutual association of roots of tropical plants and fungal hyphae.

Question 4.
List out the effects of wind on plants.
Answer:

1. The wind is one of the important factors for the formation of rain.
2. Wind promotes the aeration of water by creating waves in lakes and the ocean.
3. Soil erosion is caused by strong wind. This in turn reduces soil fertility.
4. The rate of transpiration is increased by the wind.
5. It helps in pollination in anemophilous plants.
6. The dispersal of fruits, seeds, spores, etc., is carried out by the wind.
7. The uprooting of the big trees may be caused by a strong wind.
8. The development flag forms in trees are caused by unidirectional wind.

Question 5.
List out the important edaphic factors which affect vegetation in an area.
Answer:

1. Soil moisture: Plants absorb water from the soil. Some plants absorb moisture from the atmosphere.
2. Soil water: The distribution of plants greatly depends on the soil water. The main source of soil water is rain. In soil, water is held between pore spaces of soil particles and angles between them and this forms the most important form of water available to the plants for absorption.
3. Soil reactions: The availability of soil nutrients mainly depend on the pH of the soil. Soil may be acidic, alkaline, or neutral in its reaction. The pH range of 5.5 to 6.8 is ideal for the cultivation of crop plants.
4. Soil nutrients: All essential plant nutrients such as mineral and organic nutrients in the form of ions decide the fertility of the soil, which determines the plant growth and vegetation.
5. Soil temperature: As low temperature reduces the use of water and solute absorption by roots, the geographical distribution of plants is mainly decided by soil temperature.
6. Soil atmosphere: The spaces between soil particles are occupied by oxygen and carbon-di-oxide. This forms soil aeration or soil atmosphere.
7. Soil Organisms: Many organisms like bacteria, fungi, algae, protozoans, nematodes, insects, earthworms, etc., are present in the soil. They are responsible for making the soil suitable for plant growth.

TN Board 12th Bio Botany Important Questions

Choose the correct answers:

1. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

2. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(c) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(c) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)

3. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

4. Match the following:

(a) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)
Answer:
(a) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

5. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(ii); (q)-(iii); (r)-(iv); (s)-(i)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

6. Choose the odd one out.
(a) Rhizobium
(b) Cuscuta
(c) Anabaena
(d) Nostoc
Answer:
(b) Cuscuta

7. Find out the odd one out (Defensive mechanism).
(a) Nicotine
(b) Quinine
(c) Penicillin
(d) Caffeine
Answer:
(c) Penicillin

8. Indicate the odd one out.
(a) Mimicry
(b) Myrmecophily
(c) Co-evolution
(d) Epiphyte
Answer:
(d) Epiphyte

9. Choose the odd one out.
(a) Balanophora
(b) Loranthus
(c) Nepenthes
(d) Sandalwood
Answer:
(c) Nepenthes

10. Identify the odd one out:
(a) Nelumbo
(b) Morsilea
(c) Nymphaea
(d) Utricularia
Answer:
(d) Utricularia

11. Which of the following is the correct pair:

Answer:
(b)

12. Which of the following in the incorrect pair?

Answer:
(c)

13. Which of the following in the correct pair?

Answer:
(b)

14. Choose the incorrect pair:

Answer:
(d)

15. Which of the following in the correct pair seed dispersal?

Answer:
(a)

16. Assertion: Mango plants cannot grow in temperate countries like Canada.
Reason: They are stenothermal plants and they cannot tolerate a wide range of temperatures.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is correct.
(d) Both Assertion and Reason are false.
Answer:
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.

17. Assertion: Temperature affects all biochemical reactions in the plant body.
Reason: It influences CO₂ and O₂ solubility in biological systems.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is correct.
(d) Both Assertion and Reason are false.
Answer:
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.

18. Assertion: Gases let out to the atmosphere causes climate change.
Reason: It is due to the Albedo effect.
(a) Both Assertion and Reason are correct. The reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct. The reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is correct.
(d) Both Assertion and Reason are false.
Answer:
(b) Both Assertion and Reason are correct. The reason is not the correct explanation of Assertion.

19. Assertion: Epiphytic plants like orchids get their nutrients and water from the atmosphere.
Reason: Because they have hygroscopic roots, which contain a special type of spongy tissue called velamen.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is correct.
(d) Both Assertion and Reason are false.
Answer:
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.

20. Assertion: Vallisneria is adapted to both aquatic and terrestrial modes of life.
Reason: It is an amphibious hydrophyte.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is correct.
(d) Both Assertion and Reason are false.
Answer:
(d) Both Assertion and Reason are false.

21. Eichhornia is a:
(a) Rooted floating hydrophyte
(b) Free-floating hydrophyte
(c) Submerged floating hydrophyte
(d) Amphibious hydrophyte
Answer:
(b) Free-floating hydrophyte

22. The interaction between mango free and ants called:
(a) Mimicry
(b) Co-evolution
(c) Myrmecophily
(d) Amensalism
Answer:
(c) Myrmecophily

23. Forest fire is classified under:
(a) Climatic factor
(b) Edaphic factor
(c) Topographic factor
(d) Biotic factor
Answer:
(a) Climatic factor

24. Organisms that can live in water with a wide range of salinity is called:
(a) Stenothemal
(b) Eurythermal
(c) Euryhaline
(d) Stenohaline
Answer:
(c) Euryhaline

25. Seed dispersal in Gyrocarpus in by:
(a) Hydrochoiy
(b) Zoochory
(c) Autochory
(d) Anemochory
Answer:
(d) Anemochory

26. Which of the following statement is correct?
(a) The pneumatophores are a special type of positively geotropic roots in Avicennia.
(b) They absorb water and nutrients from the atmosphere.
(c) The pneumatophores are a special type of negatively geotropic roots in Avicennia.
(d) They are called hydrographic roots.
Answer:
(c) The pneumatophores are a special type of negatively geotropic roots in Avicennia.

27. Indicate the incorrect statement.
(a) Phylloclades are present in Opuntia.
(b) Phyllode is present is Acacia
(c) Cladode is seen in Asperagus.
(d) All the above statements are not correct.
Answer:
(d) All the above statements are not correct.

28. Choose the correct statement.
(a) In desert plants the root system is not well developed.
(b) In xerophytes, the stems and leaves are covered with wax coating.
(c) In xerophytes, the vascular bundles are not well developed.
(d) None of the above.
Answer:
(b) In xerophytes, the stems and leaves are covered with a wax coating.

29. Find out the incorrect statement.
(a) Cuscuta is a total stem parasite
(b) Balanophora is a hemi parasite
(c) Rafflesia is a total root parasite
(d) Viscum is a partial stem parasite
Answer:
(b) Balanophora is a hemi parasite

30. Which of the following statement is correct?
(a) The nitrogen filing bacteria Rhizobium is present in the coralloid roots in cycas.
(b) The cyanobacterium Anabaena is present in the root nodules of leguminous plants,
(c) The interaction of water fern Azolla and nitrogen-fixing cyanobacterium is an example of mutualism.
(d) None of the above.
Answer:
(c) The interaction of water fern Azolla and nitrogen-fixing cyanobacterium is an example of mutualism.

Students get through the TN Board 12th Bio Botany Important Questions Chapter 5 Plant Tissue Culture which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 5 Plant Tissue Culture

Very short answer questions

Question 1.
Mention any two Indian scientists who worked on the tissue culture of plants.
Answer:

1. Kanta
2. Maheswari

Question 2.
Define Totipotency.
Answer:
Totipotency is defined as the genetic potential of a plant cell to give rise to a complete individual plant in a nutrient medium.

Question 3.
What is meant by explant?
Answer:
The explant is the tissue taken from a selected plant for tissue culture under invitro condition to establish a new plant.

Question 4.
Define Sterilization.
Answer:
Sterilization refers to a technique used to get rid of microbial contamination by bacteria and fungi in tissue culture practice.

Question 5.
Define Embryogenesis.
Answer:
Embryogenesis is the process through which the callus cells undergo differentiation to produce somatic embryos called Embryoids.

Question 6.
Name any two vitamins used in plant tissue culture works.
Answer:

1. Nicotinic acid
2. Pyridoxin HCl

Question 7.
Define Organogenesis.
Answer:
Organogenesis is defined as a process of the morphological changes in callus cells leading to the formation of shoot and roots.

Question 8.
What is meant by ‘Synthetic seeds’?
Answer:
Synthetic or artificial seeds are developed, from somatic embryos, which are encapsulated by inert materials like agarose and sodium alginate.

Question 9.
What is Gene Bank?
Answer:
A Gene bank is a place or laboratory, where the genetic material or germplasm of elite breeding lines of plants are stored for safe maintenance. This germplasm can be used for future use in research and revival of the plant.

Question 10.
What do you understand by intellectual property rights (IPR)?
Answer:
Intellectual Property Right is the right of property, which involves human intellect.
It consists of copyrights, patents, and trademarks.

Question 11.
Define Biosafety.
Answer:
Biosafety is defined as a procedure through which the prevention of large-scale loss of biological integrity focusing both on ecology and human health due to the advancement and application of Biotechnology.

Question 12.
Name any two apex bodies for the implementation of biosafety guidelines.
Answer:

1. Institutional Biosafety Committees (IBSCs)
2. Genetic Engineering Approval Committee (GEAC)

Short answer questions

Question 1.
Explain the term dedifferentiation.
Answer:
Dedifferentiation is the phenomenon of the revision of mature plant cells to the meristematic state and they actively divide, forming the callus in the nutrient medium. The phenomena of redifferentiation and dedifferentiation are the inherent property of plant cells or tissues. This property is described as totipotency.

Question 2.
How do you sterilize a plant tissue culture room?
Answer:
The tissue culture room sterilization starts with washing of floor and walls with detergent water and then wiped with 2% sodium hypochlorite or 95% ethanol. The cabinet of the laminar airflow chamber and the working space is wiped with 95% ethanol and subjected to uv radiation for 15 minutes, in order to get rid of all microbes in the culture room.

Question 3.
Distinguish between differentiation and Redifferentiation.
Answer:

Differentiation	Redifferentiation
Differentiation is a process of biochemical and structural changes in cells, leading to specialized form to perform a particular function.	Redifferentiation is the process through which the differentiated cells transform into another type of cells. Formation of whole plant from callus is the example of redifferentiation.

Question 4.
How do you induce callus formation, in the nutrient medium?
Answer:
In sterilized MS nutrient medium, the explant of size 1-2 cm sterile segment of leaf, stem, tuber, or root is placed. The nutrient medium is supplemented with growth hormones like auxins. The explants in the medium are ” incubated at 25 ± 2°C in the culture chamber ‘ with alternate light and dark period of 12 hrs to induce cell division. The cells on the upper surface of the explant start dividing to form a callus, which is a mass of unorganized cells or tissues, grown invitro in a culture medium.

Question 5.
Explain the process of hardening.
Answer:
The plantlets developed in the culture room need hardening to withstand the changes in the field. Therefore they are transferred to a greenhouse or hardening chamber. After some time they are transferred to normal environmental conditions. Hardening is the process in which the plantlets developed in vitro conditions are slowly exposed to diffused light for acclimatization so as to enable them to grow under normal field conditions.

Question 6.
Describe the method of Isolation of protoplast.
Answer:
Protoplasts are the plant cells without a cell wall, encircled by a cell membrane.
The small plant bits or tissue-like leaf tissue are used to prepare protoplasts. The leaf bits are immersed in 0.5% microzyme or Onizuka cellulase enzymes dissolved in 13% sorbitol or mannitol at pH 5.4. It is then kept for overnight incubation at 25°C. The protoplasts are obtained by gentle teasing of cells. The protoplasts are transferred to 20% sucrose solution in order to retain their viability. The pure protoplasts are obtained by centrifugation, which removes all debris of cell walls.

Question 7.
Give the different types of metabolites their sources and uses.
Answer:

Secondary metabolites	Plant source	Uses
Digoxin	Digitalis purpuria	Cardiac tonic
Codeine	Papaver sominiferum	Analgesic
Capsaicin	Capsicum annum	Rheumatic pain treatment
Vincristine	Catharanthus roseus	Anti-carcinogenic
Quinine	Cinchona officinalis	Antimalarial

Question 8.
Distinguish between Somaclonal variation and Gametoclonal variations.
Answer:

Somaclonal variation	Gametoclonal variations
The variations found in leaf, stem, root, tuber or propagule of the plants regenerated in invitro conditions are named as somaclonal variations.	The variations found in gametes and gametophytes of plants regenerated in vitro gametic origin are known as gametoclonal variation.

Long answer questions

Question 1.
Describe the production of secondary metabolites in plants.
Answer:
The secondary metabolites like alkaloids, flavonoids, terpenoids, phenolic compounds and recombinant proteins are produced through cell suspension culture. The secondary metabolites are not required by the plant. But they are produced in the plant as ‘by product’ of cell metabolism.
For commercial production of secondary metabolites, the bioreactors are used for scaling up the production by means of automation. Biotransformation, elicitation, and immobilization are strategies used, making cell suspension culture more efficient in the production of secondary metabolites. The examples of industrially producing important plant secondary metabolites are listed in the table.
…. For table refer to page 78, Q.No. 7.

Question 2.
Describe the important steps involved in the micropropagation of the banana plant.
Answer:

Question 3.
What are the advantages of artificial seeds?
Answer:
Artificial seeds are produced by encapsulation of embryoids with sodium alginate or agrose. They have many advantages over true seeds. These are as follows.

1. At a time millions of artificial seeds can be prepared at low cost.
2. Genetically engineered plants with desirable characteristics can easily be made through this method.
3. The genotype of a plant can easily be tested.
4. Using the cryopreservation technique artificial seeds can be stored easily for a long time.
5. The artificial seed produces identical plants.
6. As the growth of the artificial seed is faster with shortened life cycle the dormancy period of these seeds is considerably reduced.

Question 4.
What are the main components of Intellectual Property Right (IPR).
Answer:
The primary components of IPR include copyright, patents, and trademark. Other types of rights include trade secrets, publicity rights, moral rights, and the right against unfair competition.

1. In biotechnology, the transformed microorganisms and plants, and technologies for the production of commercial products are the exclusive property of the discoverer.
2. The discoverer has the full right of the property and others cannot use it without legal permission.
3. The right of the discoverer should be protected by framing laws by a country.
4. The IPR is protected by different ways like copyrights, patents, trade secrets, and trademarks.

Question 5.
What are the applications of plant tissue culture?
Answer:
Plant tissue culture has many applications:

1. Somatic hybridization provides an opportunity for the production of improved hybrids in plants.
   Somatic embryoids help in the production of artificial seeds, which help in the conservation of plant biodiversity.
2. The disease-resistant plants can be produced by the meristem and shoot tip culture technique.
3. Stress tolerant plants such as herbicide-tolerant and heat resistant plants can also be produced.
4. Large-scale propagation of tree plants and cultivable plants can be produced through micropropagation throughout the year.
5. The cell suspension culture provides the production of secondary metabolites in plants, which are utilized in pharmaceutical, cosmetic, and food industries.

Question 6.
Write the protocol for virus-free meristem tip culture.
Answer:

Choose the correct answer:

1. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

2. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(d) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
Answer:
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)

3. Match the following:

(a) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
Answer:
(a) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)

4. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
Answer:
(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)

5. Somatic embryogenesis is now reported in:
(a) Mango
(b) Potato
(c) Rice
(d) Cucumber
Answer:
(c) Rice

6. Organogenesis can be induced by:
(a) Glycine
(b) Vitamin
(c) Aspartic acid
(d) Auxin
Answer:
(d) Auxin

7. The phenomenon in which the mature cells are transformed into meristamatic state is called:
(a) Differentiation
(b) Dedifferentiation
(c) Redifferentiation
(d) Totipotency
Answer:
(b) Dedifferentiation

8. Cryopreservation is a process of preserving plant materials by cooling to very low temperature of:
(a) -190°C
(b) -195°C
(c) -185°C
(d) -20°C
Answer:
(b) -195°C

9. Virus free plants are produced by a method called:
(a) Protoplast culture
(b) Organ culture
(c) Apical meristem culture
(d) Tissue culture
Answer:
(c) Apical meristem culture

10. Choose the odd man out:
(a) Carlson
(b) Chiton
(c) Kanta
(d) T.H Morgan
Answer:
(d) T.H Morgan

11. Find the odd one out:
(a) Magnesium sulfate
(b) Auxin
(c) Nicotinic acid
(d) Potassium nitrate
Answer:
(b) Auxin

12. Identify the odd one out.
(a) Artificial seed
(b) Embryoids
(c) Somatic hybrid
(d) Plantlets
Answer:
(c) Somatic hybrid

13. Choose the odd one out.
(a) Agar
(b) Kinetin
(c) Myo-inositol
(d) Glucose
Answer:
(a) Agar

14. Indicate the odd one out:
(a) Capsicum annum
(b) Catharanthus roseus
(c) Oryza sativa
(d) Cinchona officinalis
Answer:
(c) Oryza sativa

15. Choose the correct pair:
(a) Digoxin – Analgesic
(b) Codeine – Cardiac tonic
(c) Quinine – Antimalarial
(d) Vincristine – Antibacterial
Answer:
(c) Quinine – Antimalarial

16. Which of the following is the incorrect pair?
(a) Cell culture – Liquid medium
(b) Somatic Hybrid – Fusion of protoplast
(c) Protoplast culture – Ms liquid medium
(d) Organ culture – Polyethylene glycol
Answer:
(d) Organ culture – Polyethylene glycol

17. Choose the correct pair:
(a) Micropropagation – Coconut plant
(b) Secondary metabolites – Cosmetics
(c) Sonaclonal – Heat resistant
(d) Gametoclonal – Herbicide-resistant
Answer:
(b) Secondary metabolites – Cosmetics

18. Assertion and Reason:
Assertion: Artificial seeds are produced by using embryoids obtained through in-vitro culture.
Reason: They may be derived from single cells from any part of the plant.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Both Assertion and Reason are not correct.
Answer:
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.

19. Assertion: MS nutrient medium is commonly used in tissue culture.
Reason: It has carbon sources, with suitable vitamins and hormones essential for plant growth.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Both Assertion and Reason are not correct.
Answer:
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.

20. Assertion: The callus cells undergo redifferentiation and produce somatic embryos.
Reason: The embryoids are sub-cultured to produce plantlets.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Both Assertion and Reason are not correct.
Answer:
(c) Assertion is not correct, Reason is correct.

21. Assertion: Quinine is produced by the cells of Capsicum annum through in-vitro culture.
Reason: Quinine is used as an anticarcinogenic agent.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Both Assertion and Reason are not correct.
Answer:
(d) Both Assertion and Reason are not correct.

22. Which of the following statement is correct?
(a) The process of production of metabolites can be scaled up and automated using bioreactors.
(b) Biosynthesis of indole alkaloids is carried out by Capsicum annum.
(c) Biosynthesis of indole alkaloids is carried out by Vinca rosea.
(d) None of the above.
Answer:
(a) The process of production of metabolites can be scaled up and automated using bioreactors.

23. Choose the incorrect statement.
(a) Improved hybrid plants can be produced through somatic hybridization.
(b) Somatic hybrids can be encapsulated into synthetic seeds.
(c) Production of disease-resistant plants can be carried out by cell suspension culture.
(d) Production of metabolites through cell suspension culture.
Answer:
(c) Production of disease-resistant plants can be carried out by cell suspension culture.

24. Find out the correct statement.
(a) Glycerol is used as a cryopreservation agent in the cryopreservation of plant material.
(b) Glycerol is used as a protective agent in the cryopreservation of plant material.
(c) Auxin is used as a cryoprotectant in the cryopreservation of plant materials.
(d) None of the above.
Answer:
(b) Glycerol is used as a protective agent in the cryopreservation of plant material.

25. Choose the incorrect statement.
(a) Vasil and Hildebrandt developed in-vitro production of haploid embryos from the anthers of Datura.
(b) Guha and Maheshwari produced calli and free cells in tissue culture of Tradeseantia reflex.
(c) Carlson regenerated tobacco plants from isolated mesophyll protoplasts.
(d) All the above statements are correct.
Answer:
(d) All the above statements are correct.