Site of photosynthesis and the pigments — practice questions

Question 1 · difficulty L1 · recall

Which chloroplast structure contains the photosynthetic pigments that absorb light?

• A. Thylakoids
• B. Stroma
• C. Outer envelope
• D. Starch grain

Question 2 · difficulty L1 · recall

Which pigment is the chief photosynthetic pigment in higher plants?

• A. Chlorophyll b, the major accessory green pigment
• B. Chlorophyll a
• C. Xanthophyll
• D. Carotene

Question 3 · difficulty L2 · understanding

Match List-I with List-II List - I List - II A Chlorophyll a I Yellow-green B Chlorophyll b II Yellow C Xanthophylls III Blue-green D Carotenoids IV Yellow to Yellow-orange Choose the option with all correct matches.

• A. A-I, B-II, C-IV, D-III
• B. A-I, B-IV, C-III, D-II
• C. A-III, B-IV, C-II, D-I
• D. A-III, B-I, C-II, D-IV

Question 4 · difficulty L2 · understanding

Why are carotenoids useful in photosynthesis even though chlorophyll a is the chief pigment?

• A. They replace chlorophyll a in the reaction centre
• B. They fix carbon dioxide directly
• C. They broaden light absorption
• D. They split water during photolysis

Question 5 · difficulty L3 · understanding

Match List - I with List - II. List - I List - II (A) Chlorophyll a (I) Yellow to yellow orange (B) Chlorophyll b (II) Yellow green (C) Xanthophyll (III) Blue green (D) Carotenoid (IV) Yellow Choose the correct answer from the options given below :

• A. (A)-(III), (B)-(II), (C)-(IV), (D)-(I)
• B. (A)-(III), (B)-(I), (C)-(IV), (D)-(II)
• C. (A)-(II), (B)-(III), (C)-(I), (D)-(IV)
• D. (A)-(IV), (B)-(III), (C)-(II), (D)-(I)

Question 6 · difficulty L3 · understanding

Given below are two statements : Statement I : RuBisCO is the most abundant enzyme in the world. Statement II : Photorespiration does not occur in C$$_4$$ plants. In the light of the above statements, choose the most appropriate answer from the options given below :

• A. Statement I is correct but Statement II is incorrect
• B. Statement I is incorrect but Statement II is correct
• C. Both Statement I and Statement II are correct
• D. Both Statement I and Statement II are incorrect

Question 7 · difficulty L3 · application

A leaf absorbs blue and red light strongly but reflects much of the green light falling on it. Which observation does this best explain?

• A. Red light is completely unused in photosynthesis
• B. Green light drives photosynthesis most efficiently
• C. Chlorophyll absorbs only green wavelengths
• D. Leaves usually appear green

Question 8 · difficulty L3 · analysis

An action spectrum shows high photosynthetic activity in blue and red light, while an absorption spectrum of chlorophyll shows strong absorption in the same regions. What is the best inference?

• A. Pigment absorption broadly matches photosynthetic effectiveness
• B. Only chlorophyll b participates in photosynthesis
• C. Green wavelengths are absorbed more strongly than red wavelengths
• D. The action spectrum measures pigment concentration rather than photosynthetic rate

Question 9 · difficulty L3 · application

A chloroplast fraction contains stacked membrane discs but very little soluble stromal material. Which process should remain most directly supported?

• A. Calvin-cycle carbon fixation
• B. Light-driven electron transport
• C. RuBP regeneration by stromal enzymes alone
• D. Sucrose synthesis in the cytosol