Photosynthesis

1. Excitation of P700

a) greatly reduces its reduction potential c)greatly increases its reduction potential

b) has no effect on the reduction potential d)has effects on oxidation potential only.

2. The energy required to excite PSI is

a) less than that needed to excite PSII c) more than that needed to excite PSII

b) equal to that needed to excite PSII d) it can’t be told

3. Cytochrome b₆f complex is present:

a) in the grand lamellae c) in the stromal lamellae

b) throughout the thyllakoid membrane d) exclusively in stroma

4. Which of the following is not “one electron carrier”?

a) Cytochrome b) Fe-S protein c) Quinone d) None

5. During light reaction, the direction of proton flow is from

a) Stroma to thyllakoid membrane c)Thyllakoid membrane to stroma

b) Stroma to out of chloroplast d) Lamellae to lumen

6. During cyclic electron flow which of the following is produced?

a) ATP b) NADH c) NADPH d)O_{2 e)} all

7. No. of photons required to evolve O2 during oxygenic photosynthesis is

a) 4 b) 6 c) 8 d) 10

8. Which of the following is a soluble-Cu containing electron transfer protein?

a) Cytochrome b) Pheophytin c) Plastoquinone d) Plastocyanin

9. Plastocyanin is present on which side?

a) Stroma b) Lumen c) Lamellae d) All

10. During the electron flow from Cytochrome b₆f to plastocyanine which side has maximum protons?

a) Stroma b) Lumen c) Lamellae d) Grana

11. Cytochrome c₆ in Cyanobacteria is homologous to

a) Mitochondrial cytochrome c b) Plastocyanin as in plants

c) Mitochondrial cytochrome bc₁ d) a & b e) a,b & c

12. How does ATP synthesized in chloroplasts get into the cytosol?
A. It is transported as sucrose.
B. It is transported directly by a membrane transporter.
C. It is transported as triose phosphate.
D. It is transported as inorganic phosphate (P_i).

13. The net outcome of light reaction in green plant is:

a)3ATP & 3NADPH b)2NADPH & 2ATP c)3ATP & 2NADPH d)2ATP & 3 NADPH

14. The large and small subunits of Rubisco are encoded respectively in the

a) Chloroplast and nuclear genome b) nuclear and chlorophyll genome

c) both in nuclear genome d) Bone in chlorophyll genome

15. Chlorophyll contains all glycolytic enzymes except

a) Phosphoglycerate mutase b) Phosphoglycerate isomerase c) Triose –P- mutase d) Triose – P – isomerase

16. Glycine decarboxylase is present at very high levels in mitochondria of:-

a) C₄ plants b) CAM plants c) C₃ plants d) None

17. 11. Which of the following reactions is catalyzed by transketolase?
A. glyceraldehyde 3-phosphate + dihydroxyacetone phosphate fructose 1,6-bisphosphate
B. ribose 5-phosphate ribulose 5-phosphate
C. ribulose 5-phosphate ribulose 1,5-bisphosphate
D. fructose 6-phosphate + glyceraldehyde 3-phosphate erythrose 4-phosphate + xylulose 5-phosphate

18. CO₂ fixed by mesophyll cells gets transported to neighboring bundle-sheath cells by
A. the movement of oxaloacetate that diffuses between the neighboring cell membranes.
B. the movement of oxaloacetate that passes through channels that connect the cells.
C. the movement of malate that passes through channels that connect the cells.
D. the movement of pyruvate that passes through channels that connect the cells.

19. “Nocturnal inhibitor” 2-carboxyarabinitol1-phosphate is a structural analog of

a) Ribulose 1,5-bisphosphate b) Enediolate intermediate

c) Beta ketoacid intermediate d) Hydrated intermediate.

20. Central to the rubisco activity is the carbamoylated ____ residue

a) Lys201 b) lys 175 c) His 294 d) Leu 101.

21. Which of the following represents the sequence of electron flow in the light reactions of photosynthesis in higher plants?

(A) H2O → photosystem I → photosystem II → NADP

(B) H2O → photosystem II → photosystem I → NADP

(C) H2O → photosystem II → photosystem I → ATP

(D) NADPH → photosystem I → photosystem II → O2

(E) Photosystem I → photosystem II → NADPH → O₂