Plant Physiology – Photosynthesis

1. Photosynthetic pigments are located in

a) stroma

b) grana

c) cytoplasm

d) thylakoids

2. The Dark reaction of photosynthesis was worked out by:

a) Hatch and Slack

b) Melvin Clavin

c) Arnold

d) Emerson

3. During photosynthesis oxygen is evolved from

a) carbohydrates

b) proteins

c) sunlight

d) water

4. Light reaction occur in

Chloroplast: Photosynthetic apparatus

a) Grana

b) stroma

c) thylakods

d) mitochondria

5. Photosynthetic pigments absorb

a) UV radiation

b) IR radiation

c) Visible radiation

d) Gama radiation

6. In cyclic photophorylation the high energy electrons are driven out from

a) Chlorophyll a 683

b) P 700

c) Chlorophyll a 673

d) P 870

7. One among the following elements is very important for photolysis of water

a) Mg

b) Mn

c) Fe

d) Zn

8. The hypothesis that all photosynthesis organisms require a source of hydrogen was first

proposed by

a) Van Niel

b) Hatch and Slack

c) Hill

d) Ruber and Kamen

9. In the photosynthesis process, PS II absorbs energy at or just below

a) 700 nm

b) 870 nm

c) 680 nm

d) 780 nm

10. The amount of ATP required for the synthesis of one glucose molecule in C4 pathway is

a) 18 ATP

b) 30 ATP

c) 12 ATP

d) 24 ATP

11. In bacterial photosynthesis comes from

a) H2S

b) H2O

c) H2SO4

d) NH3

12. Isotopes popularly known to have been used in study of photosynthesis:

a) C16 and N15

b) C14 and O16

c) P32 and C12

d) C11 and P32

13. Dark reaction is traced by

a) O19

b) P32

c) X-rays

d) 14CO2

14. Photosynthesis is maximum in

a) Blue light

b) Red light

c) Blue and green light

d) Blue and red light

15. Law of limiting factor was proposed by

a) Black man

b) Hill

c) Arnold

d) Engle man

16. The process of Photosynthesis is


a) Reductive, exergonic and catabolic

b) Reductive, endergonic and catabolic

c) Reductive, endergonic and anabolic

d) Reductive, exergonic and anabolic

17. A photosynthetic organism which does not release oxygen is

a) Blue green algae

b) Green alga

c) Green sulphur Bacterium

d) Lichen

18. Who was the first to study the influence of light during photosynthesis?

a) Van Niel

b) Blackmann

c) Warburg

d) J. Ingenhouz

19. 90% of the total photosynthesis is carried out by

a) algae

b) Mesophytes

c) Pteridophytes

d) Xerophytes

20. An essential process connected with photosynthesis is

a) Synthesis of glucose

b) Photolysis of water

c) Photophosphorylation

d) Breakdown of glucose

21. The site of Dark reaction of photosynthesis is

a) grana

b) stroma

c) thaylakoids

d) Both (a) and (b)

22. Which of the following is least effective in photosynthesis?

a) Blue light

b) Green light

c) Red light

d) Sunlight

23. The hydrogen donor in bacterial photosynthesis is usually

a) Water

b) Ammonia

c) Sulphur

d) Hydrogen sulphide

24. The percentage of light energy fixed in photosynthesis is generally around

a) 0.1 %

b) 1 %

c) 10%

d) 100%

25. Light is necessary in the process of photosynthesis to

a) Split carbon dioxide

b) Produce ATP and a reducing substance

c) Release energy

d) combine carbon dioxide and water

1.     d) thylakoids11.  a) H2S21. b) stroma
2.     b) Melvin Clavin12.  b) C14 and O1622. b) Green light
3.     d) water13.  d) 14CO223. d) Hydrogen sulphide
4.     a) Grana14.  b) Red light24. b) 1 %
5.     c) Visible radiation15.  a) Black man25. b) Produce ATP and a reducing substance
6.     b) P 70016. d) Reductive, endergonic and anabolic 
7.     a) Mg17. c) Green sulphur Bacterium 
8.     a) Van Niel18. d) J. Ingenhouz 
9.     c) 680 nm19. a) algae 
10.  b) 30 ATP20. b) Photolysis of water