MCQ on 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

Answers:

1. d) thylakoids
2. b) Melvin Clavin
3. d) water
4. a) Grana
5. c) Visible radiation
6. b) P 700
7. a) Mg
8. a) Van Niel
9. c) 680 nm
10. b) 30 ATP
11. a) H₂S
12. b) C¹⁴ and O¹⁶
13. ^{d) 14CO₂}
14. ^{_{b)  Red light}}
15. ^{_{a) Black man}}

1. Photosynthesis, a process of manufacture of organic compound is 

a) Catabolic process 
b) Anabolic process 
c) Both (a) and (b) 
d) None of these

2. Land plants utilize for photosynthesis 

a) 1% of water absorbed 
b) 10% of water absorbed 
c) 0.1% of water absorbed 
d)100% of water absorbed

 
3. Who proved that oxygen evolved in photosynthesis comes from water? 

a) Mayer 
b) Melvin Calvin 
c) Hatch 
d) Ruben and  Kamen

4. The first product of photosynthesis is sugar and it is converted 

a) Into starch in all plants 
b) Into proteins 
c) Rarely into anything else 
d) Glycogen

5. The site of light reactions of photosynthesis is 

a) grana 
b) stroma 
c) thaylakoids 
d) Both (a) and (b)

6. The dark reaction in photosynthesis is called so because it 

a) Cannot occur during day time 
b) it is light dependent 
c) it is light independent 
d) occurs rapidly at night

7. Which is the most effective wavelength of light for photosynthesis? 
 

a) Green 
b) Violet 
c) Red 
d) Yellow

8. Q ₁₀ is 

a) The respiratory coefficient 
b) A temperature coefficient 
c) A scale of quality 
d) A constant in quantum equation

9. The bacterial photosynthesis differs from the green plant photosynthesis in 

a) Photolysis of water 
b) Evolution of oxygen 
c) Obtaining energy from sunlight 
d) The obtaining energy from chemical compounds

10. During photochemical reaction of photosynthesis 

a) Liberation of Oxygen 
b) Liberation of ATP and NADPH 
c) Assimilation of CO₂ 
d) Liberation of Oxygen, formation of ATP and NADPH₂ takes place

Answers 
1. b) Anabolic process 
2. a) 1% of water absorbed 
3. d) Ruben and Kamen 
4. a) Into starch in all plants 
5. a) grana 
6. c) it is light independent 
7. c) Red 
8. b) A temperature coefficient 
9. d) The obtaining energy from chemical compounds 
10. d) Liberation of Oxygen, formation of ATP and NADPH₂ takes place

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

Answers 
16. d) Reductive, endergonic and anabolic 
17. c) Green sulphur Bacterium 
18. d) J. Ingenhouz 
19. a) algae 
20. b) Photolysis of water 
21. b) stroma 
22. b) Green light 
23. d) Hydrogen sulphide 
24. b) 1 % 
25. b) Produce ATP and a reducing substance