Photosynthesis in Higher Plants — Page 4 | NEET Biology

Q31

Which of the following statements about dark reactions of photosynthesis is correct?

A They cannot proceed in the presence of light

B They take place in the thylakoid

C They use ATP and NADPH produced in light reactions

D They produce oxygen

Correct Answer

Option C

Solution

(c) Dark reactions (Calvin cycle) use ATP and NADPH from light reactions to fix CO2.

Q32

The correct sequence of events during Calvin cycle is

A Carboxylation, reduction, regeneration

B Reduction, carboxylation, regeneration

C Regeneration, reduction, carboxylation

D Carboxylation, regeneration, reduction

Correct Answer

Option A

Solution

(a) Calvin cycle: CO2 fixation (carboxylation) → reduction → regeneration of RuBP.

Q33

The process that is not carried out in C4 photosynthesis is

A Calvin cycle

B Photorespiration

C Hatch-Slack cycle

D Photophosphorylation

Correct Answer

Option B

Solution

(b) Photorespiration does not occur in C4 plants.

Q34

Splitting of water during photosynthesis is associated with

A Photosystem I

B Photosystem II

C Both PS I and PS II

D None of these

Correct Answer

Option B

Solution

(b) Water splitting (photolysis) is associated with PS II (oxygen-evolving complex).

Q35

In the chloroplast, ATP synthesis during photosynthesis occurs at

A inner membrane

B outer membrane

C thylakoid membrane

D stroma

Correct Answer

Option C

Solution

(c) ATP synthase (CF0-CF1) is embedded in the thylakoid membrane.

Q36

Photolysis of water releases which of the following?

A O2, H+ and electrons

B CO2 and O2

C H2O and CO2

D H2 and O2

Correct Answer

Option A

Solution

(a) Photolysis: 2H2O → O2 + 4H+ + 4e- (at PS II).

Q37

Which one of the following is not associated with photosystem I?

A P700 chlorophyll

B Acts first in the light reaction

C Cyclic photophosphorylation

D Non-cyclic photophosphorylation

Correct Answer

Option D

Solution

(d) Non-cyclic photophosphorylation involves both PS I and PS II; cyclic only PS I.

Q38

Stroma of chloroplast contains

A Light-dependent reactions

B Both light-dependent and light-independent reactions

C Enzymes for dark reactions

D ETS complexes

Correct Answer

Option C

Solution

(c) Stroma contains RuBisCO and enzymes for the Calvin cycle (dark reactions).

Q39

C4 plants are more efficient in photosynthesis than C3 plants due to:

A Higher leaf area

B Presence of larger number of chloroplasts in the leaf cells

C Presence of thin cuticle

D Lower rate of photorespiration

Correct Answer

Option D

Solution

(d) C4 plants lack photorespiration — hence more efficient photosynthesis.

Q40

PGA as the first CO2 fixation product was discovered in photosynthesis of :

A Bryophyte

B Gymnosperm

C Angiosperm

D Alga

Correct Answer

Option D

Solution

(d) Calvin, Benson discovered PGA as first stable product using Chlorella (alga).