MCQs l Respiration in plants -2 l NEET 2025 l NEET 2026 l Biology Class XI l ABHYAS l NTA

1.       In all the following reactions, reduction of NAD⁺ to NADH occurs, except

a.       isocitric acid → α- ketoglutaric acid

b.       malic acid→ oxaloacetic acid

c.        pyruvic acid → acetyl coenzyme

d.       succinic acid → fumaric acid

2.       In the formation of Acetyle  Co- A from pyruvic acid in mitochondria, pyruvic acid gets

a.       oxidised

b.       decarboxylated

c.        both (a) and (b)

d.       reduced and isomerised

3.       How many NADPH molecules are formed in a single turn of the Krebs cycle?

a.       4

b.       Zero

c.        3

d.       8

4.       Flow of electrons in ETS is

a.       Fe^{+ + +}  →  Cu⁺ → Fe^{+ +}

b.       Fe^{+ +} → Fe^{+ + +} 

c.        Fe⁺³ → Fe⁺² → Fe⁺³

d.       Fe⁺² → Fe⁺³ → Fe⁺²

5.       A single turn of the citric acid cycle yields

a.       2 FADH₂, 2 NADH₂, 2 GTP

b.       1 FADH₂, 2 NADH₂, 1 GTP

c.        1 FADH_2,  3 NADH₂, 1 GTP

d.       1 FADH₂, 4 NADH₂, 1 GTP

 Answer Key:

1. d

2. c

3. b

4.  c

5.  c