Biology Answer in a sentence Unit 12 – plant anatomy and plant physiology 1. What is collateral vascular bundle? A vascular bundle in which xylem and phloem lies on the same radius and xylem lies towards the centre and phloem lies towards the periphery is called the collateral vascular bundle. 2. Where does the carbon that is used in photosynthesis come from? The carbon that is used in photosynthesis come from CO2 from atmosphere. 3. What is the common step in aerobic and anaerobic pathway? Glycolysis (glucose splitting) is the common step in aerobic and anaerobic pathway. 4. Name the phenomenon by which carbohydrates are oxidized to release ethyl alcohol. Anaerobic respiration or Alcohol fermentation is the phenomenon by which carbohydrates are oxidized to release ethyl alcohol. Unit 13 – structural organism of animals 5. Give the common name of the Hirudinaria granulosa. The common name of the Hirudinaria granulosa is the Indian Cattle Leech. 6. How does leech respire? Leech respire through skin. 7. Write the dental formula of rabbit. 2 0 3 3 𝟐𝟎𝟑𝟑 Dental formula is (𝐼 0 , 𝐶 0 , 𝑃𝑀 2 , 𝑀 3) in rabbit which is written as 𝟏𝟎𝟐𝟑 8. How many pairs of testes are present in leech? There are 11 pairs of testes are present in leech. 9. How is diastema formed in rabbit? The diastema in rabbit is a gap between the incisors and premolars formed due to the absence of canine. It helps in mastication and chewing of food. 10. What organs are attached to the two bronchi? Lung, bronchioles and alveoli are the organs attached to Bronchi. 11. Which organ acts as suction pump in leech? The muscular pharynx acts as a suction pump in Leech. 12. What does CNS stand for? CNS stands for Central Nervous System. 13. Why is the teeth of rabbit called heterodont? The teeth of rabbit are of different types. So it called heterodont. 14. How does leech suck blood from the host? Leech suck blood from the host in following steps: The anterior and posterior ends of body with sucker attach to the host. The triradiate or Y shaped painless wound is formed in the skin of host by jaws. The salivary glands produce hirudin(avoid blood coagulate) Unit – 14 Transportation in plants and circulation in animals 15. Name two layered protective covering of human heart. Pericardium, double layered sac is the protective layer covering of human heart. 16. What is the shape of RBC in human blood? The shape of RBC in human blood is biconcave and disc- shaped. 17. Why is the colour of the blood red? The colour of the blood is red, due to the presence of respiratory pigment Hemoglobin. 18. Which kind of cells are found in the lymph? Lymphocytes in the lymph’s defend the body from infection. 19. Name the heart valve associated with the major arteries leaving the ventricles. Semilunar valves associated with the major arteries leaving the ventricles 20. Mention the artery which supplies blood to the heart muscle. Coronary arteries supplies blood to the heart muscle Unit – 16 plants and animal hormones 21. Which hormone promotes the production of male flowers in Cucurbits? Gibberellins promotes the production of male flowers in Cucurbits. 22. Write the name of a synthetic auxin. 2, 4 D (2, 4 Dicholorophenoxy acetic acid). 23. Which hormone induces parthenocarpy in tomatoes? Gibberelliuns are efficient in the formation of seedless fruit, inducing parthenocarpy in tomatoes. 24. What is the hormone responsible for the secretion of milk in female after child birth? Prolactin (lactogenic hormone), stimulates the production f milk after child birth. Oxytocin helps milk ejection from the mammary gland after child birth. 25. Name the hormones which regulates water and mineral metabolism in man. Parathyroid hormone, Antidiuretic or vasopressin hormone regulates water and mineral metabolism in man. 26. Which hormone is secreted during emergency situation in man? The hormones of adrenal medulla, Epinephrine (adrenaline) Norepinephrine (noadrenaline) 27. Which gland secretes digestive enzymes and hormones? Exocrine pancreas secretes pancreatic juice which plays a role in digestion. Endocrine pancreas secrete hormones 28. Name the endocrine glands associated with kidneys. Adrenal gland which is called supra renal glands is associated with kidneys. Unit – 17 Reproduction in plants and animals 29. If one pollen grain produces two male gametes, how many pollen grains are needed to fertilize 10 ovules? 10 pollens grains are needed to fertilize 10 ovules. 30. In which part of the flower germination of pollen grains takes place? The germination of pollen grains takes place in the stigma of gynoecium or pistil of flower. 31. Name two organisms which reproduces through budding. Yeast Hydra 32. Mention the function of endosperm. Endosperm provides food to the developing embryo. 33. Name the hormone responsible for the vigorous contractions of the uterine muscles. Oxytocin from the posterior pituitary is responsible for the vigorous contractions of the uterine muscles. 34. What is the enzyme present in acrosome of sperm? Hyaluronidase is the enzyme present in acrosome of sperm which helps the sperm to enter the ovum during fertilization. 35. When is World Menstrual Hygiene Day observed? Every year May 28 is observed as World Menstrual Hygiene Day. 36. What is the need for contraception? Contraception is used to prevent pregnancy, to check population growth. 37. Name the part of the human female reproductive system where the following occurs. Fertilization b. Implantation Fertilization – oviduct of the female genital tract Implantation – uterus Unit – 18 Heredity 38. What is a cross in which inheritance of two pairs of contrasting characters are studied? Dihybrid cross is a cross in which inheritance of two pairs of contrasting characters are studied 39. Name the conditions when both the alleles are identical? Homozygous alleles in which both are identical. 40. A garden pea plant produces axial white flowers. Another of the same species produced terminal violet flowers. Identify the dominant trait? Axial position – dominant trait White flowers – recessive trait Terminal position – recessive trait Violet flower – dominant trait Therefore, axial violet flower dominant over the axial white flower. 41. What is the name given to the segments of DNA, which are responsible for the inheritance of a particular character? Genes of the segments of DNA are responsible for the inheritance of a particular character. 42. Name the bond which binds the nucleotides in a DNA. The hydrogen bond binds the nucleotides in a DNA Unit – 19 Origin and Evolution of Life 43. A human hand, a front leg of a cat, a front flipper of a whale and a bat’s wing look dissimilar and adapted for different functions. What is the name given to these organs? The name of the organ is Homologous organ. 44. Which organism is considered to be the fossil bird? Fossil bird – Archaeopteryx 45. What is the study of fossils called? The study of fossils is called Palaeontology. Unit – 20 Breeding and Biotechnology 46. Give the name of wheat variety having higher dietary fibre and protein. Atlas 66, a protein rich wheat variety having higher dietary fibre and protein 47. Semi-dwarf varieties were introduced in rice. This was made possible by the presence of dwarfing gene in rice. Name this dwarfing gene. IR – 8 is a high yielding semi dwarfing rice variety. It is hybrid of Peta - Indonesia Dee-geo-woo-gen - China 48. Define genetic engineering. Genetic engineering is the manipulation and transfer of genes from one organism to another organism to create new DNA called recombinant DNA. It is called as recombinant DNA technology. 49. Name the types of stem cells. Embryonic stem cell and adult stem cell. 50. What are transgenic organisms? Plants and animals expressing a modified endogenous gene or a foreign gene is called transgenic organism. 51. State the importance of biofertiliser. Increasing the harvest yields Improving soil structure Better water relation Economical Eco-friendly More efficient framing Unit – 21 Health and Diseases 52. What are psychotropic drugs? The drugs which acts on the brain and alter the behaviour, consciousness, power thinking and perception are called psychotropic drugs. They are also known as mood alternating drugs. 53. Mention the diseases caused by tobacco smoke. Lung cancer Bronchitis Pulmonary tuberculosis 54. What are the contributing factors for Obesity? Obesity is due to Genetic factors Physical inactivity Emphysema Hypoxia Over eating Endocrine factor 55. What is adult onset diabetes? Type 2 Non-Insulin dependent diabetes Mellitus is also called as adult onset diabetes. In adult onset diabetes, insulin production by the pancreas is normal and target cells do not respond to insulin. 56. What is metastasis? The process by which cancerous cells migrate to distinct parts and affect new tissues is called metastasis. 57. How does insulin deficiency occur? Insulin deficiency occurs by the destruction of β- cells of the pancreas and blood glucose levels are increased. Unit – 22 Environmental Management 58. What will happen if trees are cut down? If trees are cut down, less rainfall, Soil erosion, global warming occurs. Ecological imbalance also takes place. 59. What would happen if the habitat of wild animals is disturbed? If the habitat of wild animals is disturbed, Wild animal becoming extinct Wild animal move towards human settlement area The biological diversity cannot be maintained. 60. What are the agents of soil erosion? High velocity wind Air current Flowing water Land slide Human activities such as deforestation, farming, mining and overgrazing by cattle 61. Why fossil fuels are to be conserved? Accumulation is very slow process and takes very long period There is no ideal alternative To control global warming. Prevent them for future, fossil fuels are to be conserved 62. Solar energy is a renewable energy. How? Solar energy is a renewable energy, free source of energy that is sustainable and totally inexhaustible. 63. How are e-wastes generated? E-wastes are generated by spoiled, out dated, non-repairable electrical and electronic devices.