1. Plant physiology deals with the study of:
(A) External structure of plants
(B) Life processes of plants
(C) Internal structure of plants
(D) Classification of plants
2. Photosynthesis takes place mainly in the:
(A) Root
(B) Stem
(C) Flower
(D) Leaf
3. The green pigment involved in photosynthesis is:
(A) Chlorophyll
(B) Xanthophyll
(C) Carotene
(D) Anthocyanin
4. Which gas is released during photosynthesis?
(A) Carbon dioxide
(B) Hydrogen
(C) Nitrogen
(D) Oxygen
5. Which organelle is the site of photosynthesis?
(A) Mitochondria
(B) Chloroplast
(C) Ribosome
(D) Nucleus
6. The light reaction of photosynthesis occurs in:
(A) Stroma
(B) Cytoplasm
(C) Thylakoid membrane
(D) Mitochondria
7. The dark reaction of photosynthesis occurs in:
(A) Grana
(B) Thylakoid
(C) Cytosol
(D) Stroma
8. Which factor does NOT affect photosynthesis?
(A) Oxygen
(B) Carbon dioxide
(C) Light
(D) Temperature
9. The process by which plants lose water vapour is called:
(A) Respiration
(B) Translocation
(C) Transpiration
(D) Guttation
10. Transpiration mainly occurs through:
(A) Lenticels
(B) Stomata
(C) Root hairs
(D) Cuticle
11. Opening and closing of stomata is regulated by:
(A) Epidermal cells
(B) Root hairs
(C) Guard cells
(D) Phloem cells
12. Which factor increases transpiration rate?
(A) Wind
(B) Low temperature
(C) High humidity
(D) Darkness
13. Loss of water in liquid form from leaf margins is called:
(A) Guttation
(B) Respiration
(C) Transpiration
(D) Exudation
14. Respiration in plants releases:
(A) Oxygen
(B) Nitrogen
(C) Carbon dioxide
(D) Hydrogen
15. The site of cellular respiration is:
(A) Mitochondria
(B) Ribosome
(C) Vacuole
(D) Chloroplast
16. Which process releases energy in plants?
(A) Photosynthesis
(B) Transpiration
(C) Translocation
(D) Respiration
17. Which compound is the end product of photosynthesis?
(A) Protein
(B) Glucose
(C) Fat
(D) Amino acid
18. Movement of water across a semi-permeable membrane is called:
(A) Diffusion
(B) Active transport
(C) Imbibition
(D) Osmosis
19. Absorption of water by seeds is called:
(A) Diffusion
(B) Imbibition
(C) Transpiration
(D) Osmosis
20. Upward movement of water in plants occurs through:
(A) Phloem
(B) Cambium
(C) Cortex
(D) Xylem
21. The movement of food in plants is known as:
(A) Translocation
(B) Transpiration
(C) Diffusion
(D) Absorption
22. Food is transported in plants mainly as:
(A) Glucose
(B) Starch
(C) Sucrose
(D) Cellulose
23. The tissue responsible for translocation of food is:
(A) Xylem
(B) Cambium
(C) Cortex
(D) Phloem
24. Which theory explains ascent of sap?
(A) Root pressure theory
(B) Transpiration pull theory
(C) Diffusion theory
(D) Mass flow theory
25. Which force helps in water absorption by roots?
(A) Osmotic pressure
(B) Diffusion
(C) Root pressure
(D) Gravity
26. Which element is a component of chlorophyll?
(A) Magnesium
(B) Iron
(C) Calcium
(D) Nitrogen
27. Which deficiency causes yellowing of leaves?
(A) Nitrogen
(B) Potassium
(C) Iron
(D) Phosphorus
28. Wilting of plants occurs due to:
(A) Excess water
(B) Reduced transpiration
(C) Increased absorption
(D) Loss of turgidity
29. Which movement is growth-dependent?
(A) Nastic movement
(B) Tropic movement
(C) Turgor movement
(D) Sleep movement
30. Bending of stem towards light is called:
(A) Geotropism
(B) Hydrotropism
(C) Thigmotropism
(D) Phototropism
31. Growth of root towards gravity is:
(A) Negative geotropism
(B) Positive geotropism
(C) Phototropism
(D) Hydrotropism
32. Which plant hormone promotes cell elongation?
(A) Auxin
(B) Abscisic acid
(C) Ethylene
(D) Cytokinin
33. Which hormone promotes fruit ripening?
(A) Gibberellin
(B) Auxin
(C) Cytokinin
(D) Ethylene
34. Which hormone delays leaf senescence?
(A) Auxin
(B) ABA
(C) Ethylene
(D) Cytokinin
35. Abscisic acid mainly acts as:
(A) Growth inhibitor
(B) Fruit ripener
(C) Growth promoter
(D) Cell divider
36. Opening of stomata during day is due to:
(A) Increase in turgidity
(B) Loss of turgidity
(C) Cell death
(D) Reduced pressure
37. Which process requires energy?
(A) Active transport
(B) Osmosis
(C) Diffusion
(D) Imbibition
38. Which element is essential for protein synthesis in plants?
(A) Nitrogen
(B) Magnesium
(C) Iron
(D) Potassium
39. Photorespiration occurs in:
(A) Chloroplast only
(B) Mitochondria only
(C) Cytoplasm
(D) Chloroplast, peroxisome, and mitochondria
40. Which enzyme fixes CO₂ in Calvin cycle?
(A) Catalase
(B) Rubisco
(C) Amylase
(D) Peroxidase
41. Which movement is independent of growth direction?
(A) Tropic
(B) Hydrotropic
(C) Geotropic
(D) Nastic
42. Closing of stomata at night is due to:
(A) Low turgor
(B) High turgor
(C) High temperature
(D) Wind
43. Which process helps in cooling of plants?
(A) Respiration
(B) Transpiration
(C) Photosynthesis
(D) Absorption
44. Which mineral is required for opening of stomata?
(A) Calcium
(B) Magnesium
(C) Potassium
(D) Iron
45. Which hormone promotes stem elongation?
(A) Gibberellin
(B) Ethylene
(C) Abscisic acid
(D) Cytokinin
46. The main force for ascent of sap is:
(A) Capillarity
(B) Root pressure
(C) Diffusion
(D) Transpiration pull
47. Which plant movement is shown by Mimosa pudica?
(A) Phototropism
(B) Geotropism
(C) Nastic movement
(D) Thigmotropism
48. Which process converts light energy into chemical energy?
(A) Respiration
(B) Photosynthesis
(C) Transpiration
(D) Fermentation
49. Which factor increases respiration rate?
(A) High temperature
(B) Low temperature
(C) Low oxygen
(D) Darkness
50. Which process is common to both plants and animals?
(A) Photosynthesis
(B) Transpiration
(C) Translocation
(D) Respiration