Photosynthesis and Plant Biology MCQs

1. What is the primary site of photosynthesis in plants?
(A) Root
(B) Stem
(C) Leaf
(D) Flower

2. Which pigment is essential for photosynthesis?
(A) Hemoglobin
(B) Melanin
(C) Chlorophyll
(D) Keratin

3. What are the main products of photosynthesis?
(A) Oxygen and Carbon Dioxide
(B) Glucose and Oxygen
(C) Water and Glucose
(D) ATP and NADPH

4. In which organelle does photosynthesis occur?
(A) Mitochondrion
(B) Nucleus
(C) Chloroplast
(D) Ribosome

5. What is the main source of energy for photosynthesis?
(A) Soil minerals
(B) Sunlight
(C) Water
(D) Oxygen

6. Which gas is absorbed by plants during photosynthesis?
(A) Oxygen
(B) Carbon dioxide
(C) Nitrogen
(D) Hydrogen

7. What role does water play in photosynthesis?
(A) Provides glucose
(B) Absorbs sunlight
(C) Supplies electrons and hydrogen
(D) Releases carbon dioxide

8. Which part of the leaf contains the most chloroplasts?
(A) Spongy mesophyll
(B) Upper epidermis
(C) Palisade mesophyll
(D) Stomata

9. What is the function of stomata in leaves?
(A) Water transport
(B) Storage of food
(C) Gas exchange
(D) Chlorophyll production

10. During which part of the day does photosynthesis occur?
(A) Only at night
(B) During daylight
(C) All the time
(D) Only in the evening