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.

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

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.

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

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.

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

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.

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

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

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.

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

Question 6.
Draw and label the structure of a gemmule of sponge.
Answer:
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 2

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.

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

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.
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 3

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

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.
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 4

Question 4.
Draw and label the events of binary fission in Amoeba and paramecium.
Answer:
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 5
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 6

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

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.
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 7

Choose the correct answers.

1. Match the following:
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 8
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 9
(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:
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 10
(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)

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

3. Match the following:
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 11
(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:
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 12
(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

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

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.

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

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.
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 13
Answer:
(c)

14. Indicate the incorrect pair.
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 14
Answer:
(b)

15. Find out the correct pair.
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 15
Answer:
(d)

16. Choose the incorrect pair.
TN Board 12th Bio Zoology Important Questions Chapter 1 Reproduction in Organisms 16
Answer:
(c)

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

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.

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

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.

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

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.