Transpirational Pull

Q.

What is transpiration pull?

Q.

Name and define the process responsible for ascent of sap

Q.

State whether the following statements are true or false.

Transpiration does not take place at night.

1. True
2. False

Q.

Give an example of a pressure potential that is negative.

Q.

Name the process/term for the statements given below:

The paper which is used to show loss of water through the stomata of a leaf.

Q.

Describe cohesive force theory.

Q. Which of the following statements are true or false? Give reason in support of your answer. [5 MARKS]
(a) Potometer is an instrument used for demonstration of transpiration occurring from the lower surface of leaf.
(b) Forests contribute in bringing rains.
(c) Hydathodes are similar to stomata in plant physiology.
(d) Atmospheric humidity promotes transpiration from a green plant.
(e) Some desert plants have sunken stomata on their leaves.

Q. The phenomenon of absorption of water that depends on water loss from aerial parts of plants (Transpiration) is

1. Active absorption
2. Passive absorption
3. Both passive and active absorption
4. None of the above

Q.

why are stomata found on the lower side of the leaf?

Q. Transpiration mostly occurs through the stomata present on the epidermis of the __________.

Q.

Transpiration occurs as long as the stomata are__.

Q. Name the following by choosing the correct option:
The force contributing to the ascent of sap to the topmost regions of the plants is:

[1 Mark]

1. Diffusion
2. Active transport
3. Transpiration pull
4. Osmotic pressure

Q. Differentiate between transpiration and evaporation.

Q.

Transpiration and root pressure cause water to rise in plants by:

1. Pushing and pulling it, respectively

2. Pulling it upward

3. Pulling and pushing it, respectively

4. Pushing it upward

Q. Assertion :The loss of water in its liquid phase from the leaves is called guttation. Reason: Guttation takes place at night only.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q.

Transpiration plays significant role in SPAC (Soil Plant Atmosphere Continuum).

1. True

2. False

Q. Water lost in guttation is

1. Pure water
2. In vapour form
3. None of the above
4. Impure water

Q.

Cohesion - Tension - Transpiration Pull model of water transport was proposed by ______.

1. Dixon

2. Joly

3. Levitt

4. Mayer

Q.

Transpiration is helpful to plants in _____.

1. opening of stomata
2. upward movement of water
3. absorption of
4. conversion of starch into sugar

Q. The water movement in taller trees like Sequoia sempervirens is mainly due to -

1. ATP

2. Transpiration pull

3. Guttation

4. Root pressure

Q. Name the following by choosing the correct option:
The force contributing to the ascent of sap to the topmost regions of the plants is:
[1 Mark]

1. Diffusion
2. Active transport
3. Transpiration pull
4. Osmotic pressure

Q.

Transpiration helps in transport of water through the ___ .

1. phloem

2. xylem

3. phloem and xylem

4. stomata

Q.

Transpiration pull will be maximum under which of the following conditions?

1. Open stomata, high intensity of light and well irrigated soil
2. Open stomata, high humid atmosphere and dry soil
3. Closed stomata, low light intensity and humid atmosphere
4. Closed stomata, low light intensity and humid atmosphere

Q.

Which one is against the theory of ascent of sap given by Dixon and Jolly?

1. Pores in tracheary elements

2. Cohesion force of water molecules

3. Adhesion force of water molecules

4. Requirement of ATP

Q. If we uproot a plant then will it do transportation and translocation ?

Q.

Why are the stomata in most plants more numerous on the lower surface of a leaf instead of being on the upper surface ?

Q. Contribution of passive water absorption to total water absorption is

1. 70%
2. 50%
3. 96-100%
4. 80-90%