Top 30 mcq question practice **Photosynthesis in Higher Plants, Respiration in Higher Plants, and Plant Growth and Development**

Here are 30 multiple-choice questions (MCQs) based on the topics of **Photosynthesis in Higher Plants, Respiration in Higher Plants, and Plant Growth and Development**, aligned with the latest syllabus and trends up to 2025:

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### **Photosynthesis in Higher Plants**

1. **Which pigment is directly involved in the conversion of light energy to chemical energy?**  

   a) Chlorophyll a  

   b) Chlorophyll b  

   c) Xanthophyll  

   d) Carotene  

2. **The primary acceptor of CO₂ in C₄ plants is:**  

   a) RuBP  

   b) PEP  

   c) PGA  

   d) OAA  

3. **The site of the Calvin cycle in chloroplasts is:**  

   a) Grana  

   b) Stroma  

   c) Thylakoid membrane  

   d) Intermembrane space  

4. **Which of the following is a product of the light reaction of photosynthesis?**  

   a) ATP  

   b) NADPH  

   c) Oxygen  

   d) All of the above  

5. **Photorespiration occurs in:**  

   a) Mitochondria  

   b) Chloroplasts  

   c) Peroxisomes  

   d) All of the above  

6. **The enzyme responsible for the fixation of CO₂ in C₃ plants is:**  

   a) PEP carboxylase  

   b) RuBisCO  

   c) Catalase  

   d) ATP synthase  

7. **The wavelength of light most effective in photosynthesis is:**  

   a) Green  

   b) Red  

   c) Blue  

   d) Both b and c  

8. **The process of splitting water during photosynthesis is called:**  

   a) Photolysis  

   b) Hydrolysis  

   c) Phosphorylation  

   d) Carbon fixation  

9. **Which of the following is a C₄ plant?**  

   a) Wheat  

   b) Rice  

   c) Maize  

   d) Potato  

10. **The chemiosmotic hypothesis in photosynthesis explains the synthesis of:**  

    a) ATP  

    b) NADPH  

    c) Glucose  

    d) Oxygen  

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### **Respiration in Higher Plants**

11. **The final electron acceptor in the electron transport chain is:**  

    a) NAD⁺  

    b) FAD  

    c) Oxygen  

    d) Cytochrome c  

12. **The net gain of ATP from one molecule of glucose during aerobic respiration is approximately:**  

    a) 2 ATP  

    b) 36 ATP  

    c) 38 ATP  

    d) 40 ATP  

13. **Glycolysis occurs in the:**  

    a) Mitochondrial matrix  

    b) Cytoplasm  

    c) Inner mitochondrial membrane  

    d) Stroma  

14. **The Krebs cycle takes place in the:**  

    a) Cytoplasm  

    b) Mitochondrial matrix  

    c) Inner mitochondrial membrane  

    d) Nucleus  

15. **Which of the following is a product of anaerobic respiration in plants?**  

    a) Lactic acid  

    b) Ethanol  

    c) Pyruvate  

    d) Both b and c  

16. **The enzyme that catalyzes the conversion of pyruvate to acetyl-CoA is:**  

    a) Pyruvate dehydrogenase  

    b) Hexokinase  

    c) ATP synthase  

    d) Cytochrome oxidase  

17. **Oxidative phosphorylation is associated with:**  

    a) Glycolysis  

    b) Krebs cycle  

    c) Electron transport chain  

    d) Calvin cycle  

18. **The energy currency of the cell is:**  

    a) NADH  

    b) ATP  

    c) FADH₂  

    d) GTP  

19. **The process of respiration that occurs in the absence of oxygen is called:**  

    a) Aerobic respiration  

    b) Anaerobic respiration  

    c) Fermentation  

    d) Both b and c  

20. **The compound that enters the Krebs cycle is:**  

    a) Pyruvate  

    b) Acetyl-CoA  

    c) Glucose  

    d) Oxaloacetate  

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### **Plant Growth and Development**

21. **The primary growth of plants is due to the activity of:**  

    a) Apical meristem  

    b) Lateral meristem  

    c) Cork cambium  

    d) Vascular cambium  

22. **Which hormone promotes cell elongation in plants?**  

    a) Auxin  

    b) Gibberellin  

    c) Cytokinin  

    d) Abscisic acid  

23. **The phenomenon of shedding of leaves, flowers, and fruits is called:**  

    a) Senescence  

    b) Abscission  

    c) Dormancy  

    d) Photoperiodism  

24. **Which of the following is a synthetic auxin?**  

    a) IAA  

    b) NAA  

    c) GA₃  

    d) Zeatin  

25. **The hormone responsible for seed dormancy is:**  

    a) Gibberellin  

    b) Cytokinin  

    c) Abscisic acid  

    d) Ethylene  

26. **Vernalization is the process of:**  

    a) Flowering in response to light  

    b) Flowering in response to low temperature  

    c) Seed germination in response to water  

    d) Leaf fall in response to drought  

27. **The pigment involved in photoperiodism is:**  

    a) Chlorophyll  

    b) Phytochrome  

    c) Carotene  

    d) Xanthophyll  

28. **Which of the following is a gaseous plant hormone?**  

    a) Auxin  

    b) Gibberellin  

    c) Ethylene  

    d) Cytokinin  

29. **The process of aging in plants is called:**  

    a) Abscission  

    b) Senescence  

    c) Dormancy  

    d) Vernalization  

30. **The hormone that promotes fruit ripening is:**  

    a) Auxin  

    b) Gibberellin  

    c) Ethylene  

    d) Cytokinin  

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Comment for answer thank you everyone. 

These questions cover key concepts from the chapters on **Photosynthesis, Respiration, and Plant Growth and Development**, and are designed to test both factual knowledge and conceptual understanding.