Factors Affecting Photosynthesis

Q. Which of the following functions does not support the statement “transpiration and photosynthesis is a compromise”?

1. Water is transported to the leaves for photosynthesis and excess water is lost by transpiration.
2. Water is lost in the form of water vapor by transpiration and cools the surface of the leaf which is useful for photosynthesis.
3. Transpiration helps in transporting minerals to all parts of the plant which are also useful in photosynthesis.
4. Transpiration results in water loss for the plants and photosynthesis results in providing food to the different parts of the plant

Q. Which among the following is NOT an amphibolic pathway?

1. TCA cycle
2. EMP pathway
3. Calvin cycle
4. Glycolysis

Q. What is the optimum temperature required for $C_3$ plants?

1. $30-{40}^{\circ }C$
2. $20-{25}^{\circ }C$
3. Above ${40}^{\circ }C$
4. Above ${25}^{\circ }C$

Q. Carbon dioxide is necessary for photosynthesis. The chemical used to remove this gas most effectively from entering a control apparatus is

1. Calcium oxide
   
   
2. Distilled water
   
3. Potassium hydroxide solution
   
4. Sodium carbonate.
   

Q. Rate of photosynthesis is dependent on ____________

1. light quality
2. light intensity
3. duration of light
4. All of the above

Q. Under high light intensity the concentration of $C{O}_2$ is 420 ppm. Which of the following statements is correct in such a scenario?

1. $C_3$ plants will die due to excess concentration of $C{O}_2$
2. $C_3$ plants will show an increase in productivity
3. $C_3$ plants will show a decrease in the rate of photosynthesis
4. $C_3$ plants will show a decrease in productivity

Q. Which of the following functions does not support the statement “transpiration and photosynthesis is a compromise”?

1. Water is transported to the leaves for photosynthesis and excess water is lost by transpiration.
2. Water is lost in the form of water vapor by transpiration and cools the surface of the leaf which is useful for photosynthesis.
3. Transpiration helps in transporting minerals to all parts of the plant which are also useful in photosynthesis.
4. Transpiration results in water loss for the plants and photosynthesis results in providing food to the different parts of the plant

Q. When the level of $C{O}_2$ used in photosynthesis is equal to the amount of $C{O}_2$ released by respiration and photorespiration it is called ___________.

1. extinction point
2. $C{O}_2$ saturation point
3. $C{O}_2$ compensation point
4. $C{O}_2$ fixation

Q. When the intensity of light is gradually increased from low to high the rate of photosynthesis ________________________.

1. increases
2. decreases
3. increases and then decreases
4. decreases and then increases

Q. Assertion: Plants utilize 5-10% of the absorbed water in photosynthesis.
Reason: Reduced leaf hydration decreases the photosynthesis.

1. Both reason and assertion are true and the reason is the correct explanation for the assertion.
2. Both the reason and assertion are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but the reason is false
4. Both the assertion and reason are false

Q. Match the following with reference to the graph given below

$\begin{array}{ccc}\text{Column-I}& & \text{Column-II}\\ \text{A}& \text{I.}& \text{Light intensity is no longer a limiting factor}\\ \text{B}& \text{II.}& \text{Light intensity is the limiting factor}\\ \text{C}& \text{III.}& \text{The saturation point for light intensity}\\ \text{D}& \text{IV.}& \text{Maximum rate of photosynthesis}\\ \text{E}& \text{V.}& \text{Some factor other than light intensity is becoming a limiting factor}\end{array}$

1. A-III, B-V, C-I, D-II, E-IV
2. A-II, B-V, C-I, D-III, E-IV
3. A-III, B-V, C-II, D-I, E-IV
4. A-II, B-I, C-V, D-IV, E-III

Q.

In photosynthesis, the most useful colors of the light spectrum are

1. green, yellow & orange.

2. red, violet & blue.

3. infrared, red & yellow.

4. red, white & blue.

Q. Plants show light saturation effect at _______ of full sunlight.

1. 10%
2. 50%
3. 70%
4. 100%