🧬 UNIT – 5: LIFE PROCESSES(Question)

🧬 UNIT – 5: LIFE PROCESSES

Learning Points

• Nutrition – autotrophic and heterotrophic

• Nutrition in human beings

• Transportation in human beings and plants

• Excretion in human beings and plants

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I. Multiple Choice Questions (1 Mark each)

1. The correct statement regarding digestion that takes place in the small intestine is
   A. Acidic food becomes alkaline due to bile.
   B. Food becomes acidic due to hydrochloric acid.
   C. Starch is digested by amylase.
   D. Protein is digested by pepsin.

2. The place where carbohydrates, proteins and fats are completely digested is
   A. Stomach B. Large intestine C. Small intestine D. Liver

3. Blood vessels that carry blood from all parts of the body to the heart are
   A. Arteries B. Capillaries C. Pulmonary arteries D. Veins

4. Blood vessels that carry deoxygenated blood from heart to lungs are
   A. Pulmonary veins B. Aorta C. Veins D. Pulmonary arteries

5. Transport of soluble photosynthetic products in plants is called
   A. Evaporation B. Osmosis C. Diffusion D. Translocation

6. The upward movement of water in plants is called
   A. Water transport B. Diffusion C. Translocation D. Evaporation

7. Removal of metabolic wastes from the body is called
   A. Circulation B. Respiration C. Excretion D. Digestion

8. Cell organelle that produces energy in cells is
   A. Ribosome B. Mitochondria C. Golgi body D. Lysosome

9. Main excretory product in human beings is
   A. Uric acid B. Urea C. Carbon dioxide D. Water

10. The exchange of gases takes place in the lungs through
    A. Alveoli B. Bronchi C. Trachea D. Diaphragm

11. The structural and functional unit of kidney is
    A. Neuron B. Nephron C. Tubule D. Duct

12. The fluid part of blood is
    A. Plasma B. Platelets C. Lymph D. RBC

13. The largest artery in the human body is
    A. Pulmonary vein B. Vena cava C. Aorta D. Capillary

14. The reason for upward pull of water in xylem is
    A. Creating upward tension B. Diffusion
    C. Osmosis D. Transpiration

15. Part of the excretory system that stores nitrogenous wastes dissolved in water is
    A. Kidney B. Ureter C. Urinary bladder D. Urethra

16. Function of transpiration in plant body is
    A. Balancing oxygen & water B. Organizing water column in xylem
    C. Transporting food D. Creating osmotic pressure

17. Process by which plants release excess water is
    A. Transpiration B. Photosynthesis C. Respiration D. Metabolism

18. The need for suction pressure in plants is
    A. To overcome ion difference B. Transport food bidirectionally
    C. Carry water to higher parts D. Remove excess water

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II. One Mark Questions

19. When is lactic acid produced in muscles?

20. How is oxygen supply more efficient in birds and mammals?

21. Name the products of anaerobic respiration.

22. Why do deer and rabbits have longer small intestines than tigers/lions?

23. Why is the respiration rate of aquatic animals faster than that of terrestrial animals?

24. Write the function of platelets.

25. Name the type of transport by which food moves from leaves to other parts of plant.

26. What is transpiration?

27. What is double circulation?

28. What is excretion?

29. What is the function of guard cells?

30. When does stomata close?

31. What is the function of alveoli in lungs?

32. “Osmotic pressure in phloem tissues of plants helps in transport of materials.” Justify.

33. “There is a time to absorb oxygen and release carbon dioxide at the beginning of respiration.” Justify.

34. What are the finger-like structures in the small intestine called?

35. What is the function of villi?

36. Why can’t humans digest grass?

37. Why is diffusion not enough to meet oxygen requirement in multicellular organisms?

38. Why are enzymes called biological catalysts?

39. What are life processes?

40. Name the two types of respiration.

41. Name the product formed when glucose is broken in cytoplasm.

42. What is nutrition?

43. Name the two types of vascular tissues in plants.

44. What is photosynthesis?

45. What is cellular respiration?

46. What are parasites?

47. The haemoglobin content in the blood of two persons is 9 g/dl and 13 g/dl respectively. Whose oxygen supply is higher?

48. In schematic diagram of blood circulation, name the blood vessels X and Y. Which one has valves?

49. State the importance of transpiration in plants.

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III. Two Mark Questions

50. Draw diagram of open stomata and label:
     i) Guard cells ii) Stomatal pore.

51. Table showing length of small intestine in animals X (40 ft) and Y (8 ft). Identify herbivore and carnivore; give reason.

52. Chapati tastes sweet when chewed slowly. Why?

53. Give reason:
     a) Ventricles of human heart have thick walls.
     b) In mammals and birds, it is necessary to separate oxygenated and deoxygenated blood.

54. Name enzyme in saliva. Write its function.

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🧬 UNIT – 5 : LIFE PROCESSES – KEY ANSWERS

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I. Multiple Choice Questions (1 mark each)

Q.No	Correct Answer	Explanation
1	✅ (A) Acidic food becomes alkaline due to bile	Bile neutralises acid and emulsifies fat
2	✅ (C) Small intestine	All food components fully digested here
3	✅ (D) Veins	Carry blood from body to heart
4	✅ (D) Pulmonary arteries	Carry deoxygenated blood to lungs
5	✅ (D) Translocation	Movement of food through phloem
6	✅ (C) Translocation	Upward movement of water via xylem
7	✅ (C) Excretion	Removal of metabolic wastes
8	✅ (B) Mitochondria	“Powerhouse” of the cell
9	✅ (B) Urea	Main nitrogenous waste in humans
10	✅ (A) Alveoli	Site of gaseous exchange
11	✅ (B) Nephron	Structural & functional unit of kidney
12	✅ (A) Plasma	Fluid part of blood
13	✅ (C) Aorta	Largest artery
14	✅ (D) Transpiration	Creates suction for water pull
15	✅ (C) Urinary bladder	Stores urine before excretion
16	✅ (B) Organizing water column in xylem	Maintains continuous water flow
17	✅ (A) Transpiration	Plants lose water through leaves
18	✅ (C) Carry water to higher parts	Provides suction pressure

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II. One Mark Questions – Key Answers

19. Lactic acid is produced during anaerobic respiration in muscles due to lack of oxygen.

20. Efficient oxygen supply in birds & mammals because they have four-chambered heart ensuring complete separation of oxygenated and deoxygenated blood.

21. Anaerobic respiration products: Ethanol, CO₂, and little energy (in microbes).

22. Deer/rabbits (herbivores) have longer small intestines to digest cellulose; tigers/lions (carnivores) have shorter ones.

23. Aquatic animals have faster respiration due to less oxygen dissolved in water.

24. Platelets help in blood clotting.

25. Phloem transport (Translocation) – movement of food materials in plants.

26. Transpiration – loss of water vapour through stomata of leaves.

27. Double circulation – blood passes through the heart twice in one complete cycle.

28. Excretion – removal of metabolic wastes from the body.

29. Guard cells control opening and closing of stomata.

30. Stomata close when water is scarce or during night time.

31. Alveoli – exchange gases (O₂ and CO₂) between lungs and blood.

32. Osmotic pressure in phloem helps translocation of food by pressure flow mechanism.

33. Diffusion of gases starts respiration – O₂ enters, CO₂ exits.

34. Finger-like structures in small intestine – Villi.

35. Villi increase surface area for absorption of digested food.

36. Humans can’t digest grass because they lack cellulose-digesting enzyme.

37. Diffusion not enough in multicellular organisms because of large size and cell distance.

38. Enzymes are biological catalysts – they speed up biochemical reactions without being used up.

39. Life processes: Basic vital activities – nutrition, respiration, transport, excretion, etc.

40. Two types of respiration: Aerobic and Anaerobic.

41. Product in cytoplasm: Pyruvic acid.

42. Nutrition: Process by which organisms obtain and utilise food.

43. Vascular tissues: Xylem and Phloem.

44. Photosynthesis: Process of converting CO₂ and water into glucose using sunlight and chlorophyll.

45. Cellular respiration: Breakdown of food molecules to release energy.

46. Parasites: Organisms that live on or in other organisms and derive nutrition from them.

47. 13 g/dL haemoglobin person has higher oxygen supply.

48. X – Pulmonary artery, Y – Pulmonary vein; pulmonary vein has valves.

49. Importance of transpiration: Helps in cooling, water transport, and mineral absorption.

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III. Two Mark Questions – Key Answers

50. Open stomata diagram:
    Label – Guard cells & Stomatal pore.
    (Guard cells curved when turgid → pore open.)

51. X – Herbivore (40 ft intestine); Y – Carnivore (8 ft intestine).
    Reason: Herbivores need longer small intestine to digest cellulose.

52. Chapati tastes sweet when chewed: Saliva contains amylase which converts starch into sugar (maltose).

53. a) Ventricles have thick walls to pump blood with pressure.
    b) Separation of blood maintains body temperature and efficient oxygen supply.

54. Enzyme in saliva: Amylase (ptyalin).
    Function: Converts starch → maltose (sugar).