{"id":3702,"date":"2020-06-13T05:44:36","date_gmt":"2020-06-13T05:44:36","guid":{"rendered":"https:\/\/tnboardsolutions.com\/?p=3702"},"modified":"2021-07-08T03:27:35","modified_gmt":"2021-07-08T08:57:35","slug":"tamil-nadu-11th-biology-model-question-paper-2-english-medium","status":"publish","type":"post","link":"https:\/\/tnboardsolutions.com\/tamil-nadu-11th-biology-model-question-paper-2-english-medium\/","title":{"rendered":"Tamil Nadu 11th Biology Model Question Paper 2 English Medium"},"content":{"rendered":"

Students can Download Tamil Nadu 11th Biology Model Question Paper 2 English Medium Pdf, Tamil Nadu 11th Biology Model Question Papers<\/a> helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.<\/p>\n

TN State Board 11th Biology Model Question Paper 2 English Medium<\/h2>\n

General Instructions:<\/p>\n

    \n
  1. \n
      \n
    1. The question paper comprises of\u00a0four<\/span>\u00a0parts. Questions for Botany and Zoology are asked separately.<\/li>\n
    2. You are to attempt all the parts. An internal choice of questions is provided wherever applicable.<\/li>\n
    3. All questions of Part I, II, III and IV are to be attempted separately.<\/li>\n
    4. Question numbers\u00a01<\/span>\u00a0to\u00a08<\/span>\u00a0in\u00a0Part I<\/span>\u00a0are Multiple Choice Questions of\u00a0one mark<\/span>\u00a0each. These are to be answered by choosing the most suitable answer from the given four alternatives and writing the option code and the corresponding answer.<\/li>\n
    5. Question numbers\u00a09<\/span>\u00a0to\u00a014<\/span>\u00a0in\u00a0Part<\/span>\u00a0II<\/span>\u00a0are\u00a0two-marks<\/span>\u00a0questions. These are to be answered in about one or two sentences.<\/li>\n
    6. Question numbers\u00a015<\/span>\u00a0to\u00a019<\/span>\u00a0in\u00a0Part III<\/span>\u00a0are\u00a0three-marks<\/span>\u00a0questions. These are to be answered in about three to five short sentences.<\/li>\n
    7. Question numbers\u00a020<\/span>\u00a0and\u00a021<\/span>\u00a0in\u00a0Part IV<\/span>\u00a0are\u00a0five-marks<\/span>\u00a0questions. These are to be answered in detail. Draw diagrams wherever necessary.<\/li>\n<\/ol>\n<\/li>\n<\/ol>\n

      Time: 3:00 Hours
      \nMaximum Marks: 70<\/p>\n

      Bio – Botany [Maximum Marks: 35]<\/span><\/p>\n

      PART – I<\/span><\/p>\n

      Answer all the questions. Choose the correct answer. [8 \u00d7 1 = 8]<\/span><\/p>\n

      Question 1.
      \nRed sea is red colour due to ……………………
      \n(a) Dermacarpa sps
      \n(b) Trichodesmium sps
      \n(c) Scytonema sps
      \n(d) Gloeocapsa sps.
      \nAnswer:
      \n(b) Trichodesmium sps<\/p>\n

      Question 2.
      \nSago is obtained from …………………..
      \n(a) Cycas revoluta
      \n(b) Pinus roxburghil
      \n(c) Pinus insularis
      \n(d) Cedrus deodara
      \nAnswer:
      \n(a) Cycas revoluta<\/p>\n

      \"Tamil<\/p>\n

      Question 3.
      \nPlants growing on the water surface are called as …………………… type of aquatic plants.
      \n(a) Emergent
      \n(b) Submerged
      \n(c) Free floating
      \n(d) Mangroves
      \nAnswer:
      \n(c) Free floating<\/p>\n

      Question 4.
      \nSynapsis occur between
      \n(a) mRNA and ribosomes
      \n(b) Spindle fibres and centromeres
      \n(c) Two homologous chromosomes
      \n(d) A male and a female gamete
      \nAnswer:
      \n(c) Two homologous chromosomes<\/p>\n

      \"Tamil<\/p>\n

      Question 5.
      \nAn example of feedback inhibition is ………………………
      \n(a) Cyanide action on cytochrome
      \n(b) Sulpha drug on folic acid synthesiser bacteria
      \n(c) Allosteric inhibition of hexokinase by glucose-6-phosphate
      \n(d) The inhibition of succinic dehydrogenase by malonate
      \nAnswer:
      \n(c) Allosteric inhibition of hexokinase by glucose-6-phosphate<\/p>\n

      Question 6.
      \nRubber is a …………………..
      \n(a) Latex
      \n(b) Resin
      \n(c) Alkaloid
      \n(d) Drug
      \nAnswer:
      \n(a) Latex<\/p>\n

      Question 7.
      \nIdentify the correct statement:
      \n(I) Sulphur is essential for amino acids Cystine and Methionine
      \n(II) Low level of N, K, S and Mo affect the cell division
      \n(III) Non-leguminous plant Aims which contain bacterium Frankia
      \n(IV) Denitrification carried out by Nitrosomonas and Nitrobacter
      \n(a) (I), (II) are correct
      \n(b) (I), (II), (III) are correct
      \n(c) (I) only correct
      \n(d) All are correct
      \nAnswer:
      \n(b) (I), (II), (III) are correct<\/p>\n

      \"Tamil<\/p>\n

      Question 8.
      \nWhich step is irrelevant with respect to aerobic respiration?
      \n(a) Glycolysis
      \n(b) Pyruvate oxidate
      \n(c) Fermentation
      \n(d) TCA cycle
      \nAnswer:
      \n(c) Fermentation<\/p>\n

      PART – II<\/span><\/p>\n

      Answer any four of the following questions. [4 \u00d7 2 = 8]<\/span><\/p>\n

      Question 9.
      \nHow milk is changed into curd, if a few drops of curd is added to it? What is the reason for its sourness?
      \nAnswer:
      \nThe change is brought by Lactobacillus lactis, a bacterium present in the curd. The sourness is due to the formation of lactic acid.<\/p>\n

      \"Tamil<\/p>\n

      Question 10.
      \nWhat are pyrenoids? Mention its role?
      \nAnswer:
      \nPyrenoids are proteinaceous bodies found in chromatophores of algae and assist in the synthesis and storage of starch.<\/p>\n

      Question 11.
      \nFrom which type of flowers does the aggregate fruit develops?
      \nAnswer:
      \nAggregate fruits develop from a single flower having an apocarpous pistil. Each of the free carpel is develops into a simple fruitlet. A collection of simple fruitlets makes an aggregate fruit.<\/p>\n

      \"Tamil<\/p>\n

      Question 12.
      \nDefine magnification. How will you calculate it?
      \nAnswer:
      \nThe optical increase in the size of an image is called magnification. It is calculated by the following formula;
      \nMagnification = \"Tamil<\/p>\n

      Question 13.
      \nDefine Diffusion Pressure Deficit (DPD)?
      \nAnswer:
      \nThe difference between the diffusion pressure of the solution and its solvent at a particular . temperature and atmospheric pressure is called as Diffusion Pressure Deficit (DPD).<\/p>\n

      \"Tamil<\/p>\n

      Question 14.
      \nName the two forms of phycobilins and also give an example?
      \nAnswer:
      \nPhycobilins exists in two form. They are:<\/p>\n

        \n
      1. Phycocyanin found in Cyanobacteria.<\/li>\n
      2. Phycoerythrin found in red algae.<\/li>\n<\/ol>\n

        PART – III<\/span><\/p>\n

        Answer any three questions in which question number 19 is compulsory. [3 \u00d7 3 = 9]<\/span><\/p>\n

        Question 15.
        \nDo you think shape of chloroplast is unique for algae? Justify your answer?
        \nAnswer:
        \nVariation among the shape of the chloroplast is found in members of algae. It is Cup shaped (Chlartiydomonas), Discoid (Chara), Girdle shaped (Ulothrix), reticulate (Oedogonium), spiral (Spirogyra), stellate (Zygnema) and plate like (Mougeoutia).<\/p>\n

        Question 16.
        \nName few molecular markers used in molecular taxonomy?
        \nAnswer:
        \nAllozymes, mitochondrial DNA, micro satellites, RFLP (Restriction Fragment Length Polymorphism), RAPD (Random amplified polymorphic DNA), AFLPs (Amplified Fragment Length Polymorphism), Single nucleotide Polymorphism – SNP, microchips or arrays.<\/p>\n

        \"Tamil<\/p>\n

        Question 17.
        \nList out the criteria for being as essential minerals?
        \nAnswer:
        \nAmon and Stout (1939) gave criteria required for essential minerals:<\/p>\n

          \n
        1. Elements necessary for growth and development.<\/li>\n
        2. They should have direct role in the metabolism of the plant.<\/li>\n
        3. It cannot be replaced by other elements.<\/li>\n
        4. Deficiency makes the plants impossible to complete their vegetative and reproductive phase.<\/li>\n<\/ol>\n

          \"Tamil<\/p>\n

          Question 18.
          \nDraw a simplified diagram showing the various regions of root?
          \nAnswer:<\/p>\n

          \"Tamil<\/p>\n

          Question 19.
          \nWhat do you mean by the term – Basipetal transport and Acropetal transport?
          \nAnswer:
          \nBasipetal means transport through phloem from shoot to root and acropetal means transport through xylem from root to shoot.<\/p>\n

          PART – IV<\/span><\/p>\n

          Answer all the questions. [2 \u00d7 5 = 10]<\/span><\/p>\n

          Question 20.
          \nDescribe in detail about the lytic cycle of phages with diagram?
          \nAnswer:
          \nLytic cycle:
          \nDuring lytic cycle of phage, disintegration of host bacterial cell occurs and the progeny virions are released. The steps involved in the lytic cycle are as follows:<\/p>\n

          (I) Adsorption:
          \nPhage (T4<\/sub>) particles interact with cell wall of host (E coli). The phage tail makes contact between the two, and tail fibres recognize the specific receptor sites present on bacterial cell surface. The lipopolysaccharides of tail fibres act as receptor in phages.<\/p>\n

          The process involving the recognition of phage to bacterium is called landing. Once the contact is established between tail fibres of phage and bacterial cell, tail fibres bend to anchor the pins and base plate to the cell surface. This step is called pinning.<\/p>\n

          (II) Penetration:
          \nThe penetration process involves mechanical and enzymatic digestion of the cell wall of the host. At the recognition site phage digests certain cell wall structure by viral enzyme (lysozyme). After pinning the tail sheath contracts (using ATP) and appears shorter and thicker.<\/p>\n

          After contraction of the base plate enlarges through which DNA is injected into the cell wall without using metabolic energy. The step involving injection of DNA particle alone into the bacterial cell is called Transfection. The empty protein coat leaving outside the cell is known as ‘ghost’.<\/p>\n

          \"Tamil<\/p>\n

          (III) Synthesis:
          \nThis step involves the degradation of bacterial chromosome, protein synthesis and DNA replication. The phage nucleic acid takes over the host biosynthetic machinery. Host DNA gets inactivated and breaks down.<\/p>\n

          Phage DNA suppresses the synthesis of bacterial protein and directs the metabolism of the cell to synthesis the proteins of the phage particles and simultaneously replication of phage DNA also takes place.<\/p>\n

          (IV) Assembly and Maturation:
          \nThe DNA of the phage and protein coat are synthesized separately and are assembled to form phage particles. The process of assembling the phage particles is known as maturation. After 20 minutes of infection about 300 new phages are assembled.<\/p>\n

          (V) Release:
          \nThe phage particle gets accumulated inside the host cell and are released by the lysis of the host cell wall.<\/p>\n

          [OR]<\/p>\n

          Draw a flow chart depicting the Bentham and Hooker Classification?
          \nAnswer:<\/p>\n

          \"Tamil<\/p>\n

          \"Tamil<\/p>\n

          Question 21.
          \nWith the help of diagram explain the possible route of water across root cells?
          \nAnswer:
          \nThere are three possible routes of water.
          \nThey are:-<\/p>\n

            \n
          1. Apoplast<\/li>\n
          2. Symplast and<\/li>\n
          3. Transmembrane route.<\/li>\n<\/ol>\n

            1. Apoplast:
            \nThe apoplast (Greek: apo = away; plast = cell) consists of everything external to the plasma membrane of the living cell. The apoplast includes cell walls, extra cellular spaces and the interior of dead cells such as vessel elements and tracheids.<\/p>\n

            In the apoplast pathway, water moves exclusively through the cell wall or the non-living part of the plant without crossing any membrane. The apoplast is a continuous system.<\/p>\n

            \"Tamil<\/p>\n

            2. Symplast:
            \nThe symplast (Greek: sym = within; plast = cell) consists of the entire mass of cytosol of all the living cells in a plant, as well as the plasmodesmata, the cytoplasmic channel that interconnects them.<\/p>\n

            In the symplastic route, water has to cross plasma membrane to enter the cytoplasm of outer root cell; then it will move within adjoining cytoplasm through plasmodesmata around the vacuoles without the necessity to cross more membrane, till it reaches xylem.<\/p>\n

            3. Transmembrane route:
            \nIn transmembrane pathway water sequentially enters a cell on one side and exits from the cell on the other side. In this pathway, water crosses at least two membranes for each cell. Transport across the tonoplast is also involved.<\/p>\n

            Mechanism of Water Absorption Kramer (1949) recognized two distinct mechanisms which independently operate in the absorption of water in plants. They are,<\/p>\n

              \n
            1. Active absorption<\/li>\n
            2. Passive absorption.<\/li>\n<\/ol>\n

              [OR]<\/p>\n

              Explain the types of parasitic mode of nutrition in angiosperms?
              \nParasitic mode of nutrition in angiosperms:
              \nAnswer:
              \nOrganisms deriving their nutrient from another organism (host) and causing disease to the host are called parasites.<\/p>\n

              a. Obligate or Total parasite – Completely depends on host for their survival and produces haustoria.<\/p>\n

              (I) Total stem parasite:
              \nThe leafless stem twine around the host and produce haustoria. Example: Cuscuta (Dodder), a rootless plant growing on Zizyphns, Citrus and so on.<\/p>\n

              (II) Total root parasite:
              \nThey do not have stem axis and grow in the roots of host plants produce haustoria. Example: Rajflesia, Orobanche and Balanophora.<\/p>\n

              b. Partial parasite – Plants of this group contain chlorophyll and synthesize carbohydrates. Water and mineral requirements are dependent on host plant.<\/p>\n

              (I) Partial Stem Parasite:
              \nExample: Loranthus and Viscum (Mistletoe) Loranthus grows on fig and mango trees and absorb water and minerals from xylem.<\/p>\n

              (II) Partial root parasite:
              \nExample: Santalum album (Sandal wood tree) in its juvenile stage produces haustoria which grows on roots of many plants.<\/p>\n

              Bio – Zoology [Maximum marks: 35]<\/span><\/p>\n

              PART – I<\/span><\/p>\n

              Answer all the questions. Choose the correct answer. [8 \u00d7 1 = 8]<\/span><\/p>\n

              Question 1.
              \nWhich is not a unit of taxonomic category?
              \n(a) Series
              \n(b) Glumaceae
              \n(c) Class
              \n(d) Phylum
              \nAnswer:
              \n(b) Glumaceae<\/p>\n

              \"Tamil<\/p>\n

              Question 2.
              \nStudy of ticks and mites is ……………………
              \n(a) Acarology
              \n(b) Entomology
              \n(c) Malacology
              \n(d) Carcinology
              \nAnswer:
              \n(a) Acarology<\/p>\n

              \"Tamil<\/p>\n

              Question 3.
              \nMatch the List – I and List – II.<\/p>\n\n\n\n\n\n\n\n
              \n

              List – I<\/strong><\/p>\n<\/td>\n

              		\n

              List – II<\/strong><\/p>\n<\/td>\n<\/tr>\n

              1. Silver fish<\/td>\n(i) Book lung<\/td>\n<\/tr>\n
              2. Scorphion<\/td>\n(ii) Pharyngeal gills<\/td>\n<\/tr>\n
              3. Sea squirt<\/td>\n(iii) Lungs<\/td>\n<\/tr>\n
              4. Dolphin<\/td>\n(iv) Trachea<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

              Answer:
              \n(a) 1 – (iv), 2 – (i), 3 – (iii), 4 – (ii)
              \n(b) 1 – (iv), 2 – (i), 3 – (ii), 4 – (iii)
              \n(c) 1 – (i), 2 – (iii), 3 – (iv), 4 – (ii)
              \n(d) 1 – (i), 2 – (iv), 3 – (iii), 4 – (ii)<\/p>\n

              \"Tamil<\/p>\n

              Question 4.
              \nMSH stands for ……………………
              \n(a) Melanocyte stimulating hormone
              \n(b) Malic stimulating hormone
              \n(c) Myosin stimulating hormone
              \n(d) Metabolic stimulating hormone
              \nAnswer:
              \n(a) Melanocyte stimulating hormone<\/p>\n

              Question 5.
              \nWhich of the following is an correct statement?
              \n(a) Ehler\u2019s – Danlos syndrome – Affects collagen and results in facial abnormalities.
              \n(b) Rhabdomyosarconca – Life threatening soft tissue tumour of head, neck and urinogenital tract.
              \n(c) Rheumatoid arthritis – Progressive inability to secrete saliva and tears.
              \n(d) Alzheiner\u2019s disease – A degenerative disorder of the nervous system that affects movement often including tremors.
              \nAnswer:
              \n(b) Rhabdomyosarconca – Life threatening soft tissue tumour of head, neck and urinogenital tract.<\/p>\n

              Question 6.
              \nWhich of the following is an incorrect statement?
              \n(a) The functions of frontal region are Behaviour, intelligence, memory and movement.
              \n(b) The functions of parietal region is intelligence and memory.
              \n(c) The functions of temporal region are speech, hearing and memory.
              \n(d) The functions of occipital region is visual processing.
              \nAnswer:
              \n(b) The functions of parietal region is intelligence and memory.<\/p>\n

              \"Tamil<\/p>\n

              Question 7.
              \nSynovial fluid is present in …………………….
              \n(a) Spinal cavity
              \n(b) Cranial activity
              \n(c) Freely movable joints
              \n(d) Fixed joints
              \nAnswer:
              \n(c) Freely movable joints<\/p>\n

              Question 8.
              \nGlands responsible for secreting tears are ………………………….
              \n(a) Glands of moll
              \n(b) Lacrimal glands
              \n(c) Meibomian glands
              \n(d) Glands of Zeis
              \nAnswer:
              \n(b) Lacrimal glands<\/p>\n

              PART – II<\/span><\/p>\n

              Answer any four of the following questions. [4 \u00d7 2 = 8]<\/span><\/p>\n

              Question 9.
              \nWhy are spongin and spicules important to a sponge?
              \nAnswer:
              \nSpongin and spicules provide support and supports the soft body parts of the sponges. The spicules give the sponges rigidity and form to the sponges.<\/p>\n

              Question 10.
              \nWhat is water vascular system?
              \nAnswer:
              \nThe system which helps in nutrition and respiration in echinoderms is called water vascular system. Water enters into the body through special organs.<\/p>\n

              \"Tamil<\/p>\n

              Question 11.
              \nDifference between chordates and non-chordates?
              \nAnswer:<\/p>\n\n\n\n\n\n\n
              \n

              S.No<\/strong><\/p>\n<\/td>\n

              		\n

              Chordates<\/strong><\/p>\n<\/td>\n

              		\n

              Non-Chordates<\/strong><\/p>\n<\/td>\n<\/tr>\n

              1.<\/td>\nNotochord is present.<\/td>\nAbsence of notochord.<\/td>\n<\/tr>\n
              2.<\/td>\nPharynx perforated by gill slits.<\/td>\nGill slits absent.<\/td>\n<\/tr>\n
              3.<\/td>\nA post anal tail is present.<\/td>\nPost anal tail is absent.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

              Question 12.
              \nDraw the diagram of head region of Periplaneta americana?
              \nAnswer:<\/p>\n

              \"Tamil<\/p>\n

              Question 13.
              \nName the different types of movement?
              \nAnswer:<\/p>\n

                \n
              1. Amoeboid movement.<\/li>\n
              2. Ciliary movement.<\/li>\n
              3. Flagellar movement.<\/li>\n
              4. Muscular movement.<\/li>\n<\/ol>\n

                \"Tamil<\/p>\n

                Question 14.
                \nWhat is endomysium?
                \nAnswer:
                \nThe connective tissue surrounding the muscle fibre is called the endomysium.<\/p>\n

                PART – III<\/span><\/p>\n

                Answer any three questions in which question number 19 is compulsory. [3 \u00d7 3 = 9]<\/span><\/p>\n

                Question 15.
                \nWhat are the classical taxonomical tools?
                \nAnswer:
                \nTaxonomical tools are the tools for the study of classification of organisms.
                \nThey include:-<\/p>\n

                Taxonomical keys:
                \nKeys are based on comparative analysis of the similarities and dissimilarities of organisms. There are separate keys for different taxonomic categories.<\/p>\n

                Museum:
                \nBiological Museums have collection of preserved plants and animals for study and ready reference. Specimens of both extinct and living organisms can be studied.<\/p>\n

                Zoological parks:
                \nThese are places where wild animals are kept in protected environments under human care. It enables us to study their food habits and behavior.<\/p>\n

                Marine parks:
                \nMarine organisms are maintained in protected environments.<\/p>\n

                Printed taxonomical tools:
                \nIt consist of identification cards, description, field guides and manuals.<\/p>\n

                \"Tamil<\/p>\n

                Question 16.
                \nDifferentiate Ehler\u2019s – Danlos syndrome and stickler syndrome?
                \nAnswer:
                \nEhler\u2019s – Danlos syndrome is the defect in the synthesis of collagen in the joints, heart valves, organ walls and arterial walls:
                \nStickler syndrome is a group of hereditary conditions affecting collagen and results in facial abnormalities.<\/p>\n

                Question 17.
                \nDefine Purkinje fibres?
                \nAnswer:
                \nTwo special cardiac muscle fibres originate from the auriculo ventricular node and are called the bundle of his which runs down into the interventricular septum and the fibres spread into the ventricles. These fibres are called the Purkinje fibres.<\/p>\n

                \"Tamil<\/p>\n

                Question 18.
                \nDraw the diagram of pelvic girdle with lower limb?
                \nAnswer:<\/p>\n

                \"Tamil<\/p>\n

                \"Tamil<\/p>\n

                Question 19.
                \nWhat are the symptoms of acromegaly?
                \nAnswer:
                \nAcromegaly is caused due to excessive secretion of growth hormone in adults. The symptoms of acromegaly are:<\/p>\n

                  \n
                1. Overgrowth of hand bones, feet bones, jaw bones.<\/li>\n
                2. Malfunctioning of gonads.<\/li>\n
                3. Enlargement of viscera, tongue, lungs, heart, liver, splean and endocrine glands like thyroid, or adrenal glands.<\/li>\n<\/ol>\n

                  PART – IV<\/span><\/p>\n

                  Answer all the questions. [2 \u00d7 5 = 10]<\/span><\/p>\n

                  Question 20.
                  \nDescribe the digestive system of Lamipto mauritii?
                  \nAnswer:
                  \nThe digestive system of the earthworm consists of the alimentary canal and the digestive glands. The alimentary canal runs as a straight tube throughout the length of the body from the mouth to anus.<\/p>\n

                  The mouth opens into the buccal cavity which occupies the 1sst<\/sup>and 22nd<\/sup> segments. The buccal cavity leads into a thick muscular pharynx,which occupies the 3rd<\/sup> and 4th<\/sup> segments and is surrounded by the pharyngeal glands.<\/p>\n

                  A small narrow tube, oesophagus lies in the 5th<\/sup> segment and continues into a muscular gizzard in the 6th<\/sup> segment. The gizzard helps in the grinding of soil particles and decaying leaves. Intestine starts from the 7th<\/sup> segment and continues till the last segment.<\/p>\n

                  The dorsal wall of the intestine is folded into the cavity as the typhlosole. This fold contains blood vessels and increases the absorptive area of the intestine. The imier epithelium consists of columnar cells and glandular cells. The alimentary canal opens to the exterior through the anus.<\/p>\n

                  \"Tamil<\/p>\n

                  The ingested organic rich soil passes through the digestive tract where digestive enzymes breakdown complex food into smaller absorbable units. The simpler molecules are absorbed through the intestinal membrane and are utilized.<\/p>\n

                  The undigested particles along with earth are passed out through the anus, as worm castings or vermicasts. The pharyngeal or salivary gland cells and the glandular cells of the intestine are supposed to be the digestive glands which secrete digestive enzymes for digestion of food.<\/p>\n

                  [OR]<\/p>\n

                  What are the effects of smoking?
                  \nAnswer:
                  \nToday due to curiosity, excitement or adventure youngsters start to smoke and later get addicted to smoking. Research says about 80% of the lung cancer is due to cigarette smoking. Smoking is inhaling the smoke from burning tobacco. There are thousands of known chemicals which includes nicotine, tar, carbon monoxide, ammonia, sulphur-dioxide and even small quantities of arsenic.<\/p>\n

                  Carbon monoxide and nicotine damage the cardiovascular system and tar damages the gaseous exchange system. Nicotine is the chemical that causes addiction and is a stimulant which makes the heart beat faster and the narrowing of blood vessels results in raised blood pressure and coronary heart diseases.<\/p>\n

                  Presence of carbon monoxide reduces oxygen supply. Lung cancer, mouth cancer and larynx is more common in smokers than non – smokers. Smoking also causes cancer of the stomach, pancreas and bladder and lowers sperm count in men.<\/p>\n

                  Smoking can cause lunb diseases by damaging the airways and alveoli and results in emphysema and chronic bronchitis. These two diseases along with asthma are often referred as Chronic Obstructive Pulmonary Disease (COPD).<\/p>\n

                  When a person smokes, nearly 85% of the smoke released is inhaled by the smoker himself and others in the vicinity, called passive smokers, are also affected. Guidance or counselling should be done in such users to withdraw this habit.<\/p>\n

                  \"Tamil<\/p>\n

                  Question 21.
                  \nExplain the structure of spinal cord?
                  \nAnswer:
                  \nThe spinal cord is a long, slender, cylindrical nervous tissue. It is protected by the vertebral column and surrounded by the three membranes as in the brain. The spinal cord that extends from the brain stem into the vertebral canal of the vertebral column up to the level of 1st<\/sup> or 22nd<\/sup> lumbar vertebra.<\/p>\n

                  So the nerve roots of the remaining nerves are greatly elongated to exit the vertebral column at their appropriate space. The thick bundle of elongated nerve . roots within the lower vertebral canal is called the cauda equina (horse\u2019s tail) because of its appearance.<\/p>\n

                  In the cross section of spinal cord, there are two indentations: the posterior median sulcus and the anterior median fissure. Although there might be slight variations, the cross section of spinal cord is generally the same throughout its length. In contrast to the brain, the grey matter in the spinal cord forms an inner butterfly shaped region surrounded by the outer white matter.<\/p>\n

                  The grey matter consists of neuronal cell bodies and their dendrites, intemeurons and glial cells. White matter consists of bundles of nerve fibres. In the center of the grey matter there is a central canal which is filled with CSF. Each half of the grey matter is divided into a dorsal horn, a ventral hom and a lateral horn.<\/p>\n

                  The dorsal horn contains cell bodies of interneurons on which afferent neurons terminate. The ventral hom contains cell bodies of the efferent motor neurons supplying the skeletal muscle. Autonomic nerve fibres, supplying cardiac and smooth muscles and exocrine glands, originate from the cell bodies found in the lateral horn.<\/p>\n

                  In the white matter, the bundles of nerve fibres form two types of tracts namely ascending tracts which carry’ sensory impulses to the brain and descending tracts which carry motor impulses from the brain to the spinal nerves at various levels of the spinal cord. The spinal cord shows two enlargements,one in the cervical region and another one in the lumbosacral region. The cervical enlargement serves the upper limb and lumbar enlargement serves the lower limbs.<\/p>\n

                  \"Tamil<\/p>\n

                  [OR]<\/p>\n

                  What are the stages involved in rearing of chicken?
                  \nAnswer:
                  \nStages involved in rearing:
                  \nThere are some steps involved in rearing of chicken.<\/p>\n

                  1. Selection of the best layer:
                  \nAn active intelligent looking bird, with a bright comb, not obese should be selected.<\/p>\n

                  2. Selection of eggs for hatching:
                  \nEggs should be selected very carefully. Eggs should be fertile, medium sized, dark brown shelled and freshly laid eggs are preferred for rearing. Eggs should be washed, cleaned and dried.<\/p>\n

                  3. Incubation and hatching:
                  \nThe maintenance of newly laid eggs in optimum condition till hatching is called incubation. The fully developed chick emerges out of egg after an incubation period of 21 – 22 days.<\/p>\n

                  There are two types of incubation namely natural incubation and artificial incubation. In the natural incubation method, only a limited number of eggs can be incubated by a mother hen. In artificial incubation, more number of eggs can be incubated in a chamber (Incubator).<\/p>\n

                  4. Brooding:
                  \nCaring and management of young chicks for 4 – 6 weeks immediately after hatching is called brooding. It can also be categorized into two types namely natural and artificial brooding.<\/p>\n

                  5. Housing of Poultry:
                  \nTo protect the poultry from sun, rain and predators it is necessary to provide housing to poultry. Poultry house should be moisture proof, rat proof and it should be easily cleanable and durable.<\/p>\n

                  6. Poultry feeding:
                  \nThe diet of chicks should contain adequate amount of water,carbohydrates, proteins, fats, vitamins and minerals.<\/p>\n","protected":false},"excerpt":{"rendered":"

                  Students can Download Tamil Nadu 11th Biology Model Question Paper 2 English Medium Pdf, Tamil Nadu 11th Biology Model Question Papers helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams. TN State Board 11th Biology Model Question Paper 2 English …<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spay_email":""},"categories":[6],"tags":[],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/tnboardsolutions.com\/wp-json\/wp\/v2\/posts\/3702"}],"collection":[{"href":"https:\/\/tnboardsolutions.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/tnboardsolutions.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/tnboardsolutions.com\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/tnboardsolutions.com\/wp-json\/wp\/v2\/comments?post=3702"}],"version-history":[{"count":0,"href":"https:\/\/tnboardsolutions.com\/wp-json\/wp\/v2\/posts\/3702\/revisions"}],"wp:attachment":[{"href":"https:\/\/tnboardsolutions.com\/wp-json\/wp\/v2\/media?parent=3702"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/tnboardsolutions.com\/wp-json\/wp\/v2\/categories?post=3702"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/tnboardsolutions.com\/wp-json\/wp\/v2\/tags?post=3702"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}