Question 1. It happens during the photosynthesis in green plants______.
(A) Taking oxygen and releasing nitrogen
(B) Taking oxygen and releasing CO2
(C) Taking CO2 and releasing oxygen
(D) Taking nitrogen and releasing oxygen
Question 2. Which one of the following gases is used by plants in photosynthesis?
(A) Sulphur dioxide
(C) Carbon dioxide
Question 3. Which of the following types of light are strongly absorbed by plants?
(A) Yellow and violet
(B) Indigo and yellow
(C) Blue and red
(D) Violet and orange
Question 4. Most of the oxygen on earth is produced by______.
(A) Paddy fields
Question 5. Photosynthesis occurs in______.
(A) Only day
(B) Day or night
(C) Day and night
Question 6. The process by which plants produce food is called_______.
(C) Metabolic synthesis
Question 7. The process by which plants synthesize their food is called______.
Question 8. Photosynthesis occurs in______.
Question 9. The most active light for photosynthesis is_______.
(A) Green light
(B) Blue light
(C) Red light
(D) Violet light
Question 10. Which light is most effective in photosynthesis?
Question 11. What rays of sunlight are mostly utilized by chlorophyll in photosynthesis?
Question 12. Artificial light can______.
(A) Not bring about photosynthesis
(B) Bring about photosynthesis
(C) Synthesise chlorophyll
(D) Destroy chlorophyll
Question 13. Light energy changes into the chemical energy by which of the following process?
(A) By spewing
(B) By respiration
(C) By photosynthesis
Question 14. Which one of the following is the process involved in photosynthesis?
(A) Oxygen is taken and carbon dioxide and water vapour are given out
(B) Food is oxidized to release carbon dioxide and water
(C) Free energy is converted into potential energy and stored
(D) Potential energy is released to form free energy
Question 15. Which of the following has the maximum efficiency to convert solar energy into chemical energy?
Question 16. Which of the following is not the work of roots?
(A) To help the plants
(B) Absorption nutrients
(C) Water absorption
Question 17. When the bark of a tree is removed in a circular fashion all around near its base, it gradually dries up or dries because_____.
(A) Roots do not receive oxygen for respiration
(B) Tree is infected by the soil microbes
(C) Roots are starved of energy
(D) Water from soil cannot rise to aerial parts
Question 18. ‘Phloem’ in plants is mainly responsible for______.
(A) Transportation of water
(B) Transportation of oxygen
(C) Transportation of amino acid
(D) Transportation of food
Question 19. Which one of the following does not increase the amount of carbon dioxide in carbon cycle on earth?
(A) Volcanic action
(B) Decay of organic matter
Question 20. Oxygen, which is liberated during photosynthesis comes from______.
(A) Phosphoglyceric acid
(C) Carbon dioxide
Question 21. Which one of the following gases is essential for photosynthesis process?