Transpiration and Photosynthesis

Q.

Why transpiration is called necessary evil?

Q.

How does light affect transpiration?

Q. Which one of the following graphs most closely represents the relationship between the rate of transpiration of a mesophytic leaf and the atmospheric humidity?

1. 
2. 
3. 
4. 

Q.

Why does carbon dioxide diffuse into leaves?

Q.

Transpiration pull is one of the causes responsible for the ascent of sap.

1. True
2. False

Q.

Fill in the blanks:

Transpiration pull theory was given by ___________ in (1894).

Q.

The leaves of a well-watered potted plant were found wilted during a hot sunny day.

d. What advantage would the plants have derived from wilting?

Q. Water lost by transpiration is ______.

1. rich in organic and inorganic solutes
2. rich in organic salts
3. rich in dissolved salts
4. pure water

Q.

Name the following:

Development of negative pressure due to transpiration.

Q.

Phosphorus is a macro nutrient required for opening and closing of stomata

1. True
2. False

Q. Explain why transpiration in higher plants is considered a necessary evil.

Q. An antitranspirant is

1. Cobalt chloride
2. Mercury
3. Phenyl mercuric acetate
4. Potassium

Q. How does transpiration pull help in absorption of water by the plants?

Q. Which of the following is not due to transpiration?

1. Transport of minerals
2. Maintenance of turgidity of leaves
3. Transport of organic substances
4. Absorption and transport of water

Q.

The most important function of transpiration in plants is to cause______.

Q. When the temperature of water is 0^o C^, then the water absorption.

1. decreases
2. not affected
3. The soil will lose capillary H₂O
4. Increases

Q. Approx. _______ of the water absorbed by a plant is lost in transpiration.

1. 20-40%
2. 98-99%
3. 1-2%
4. 6-8%

Q. In plants, the transpiration pull theory for ascent of sap was first proposed by

1. Dixon.
2. Dixon and Jolly.
3. J.C. Bose.
4. Strasburter.

Q. Application Based Questions .
Why does transpiration occur mainly through leaves ?

Q. Short / Long answer type questions.
Transpiration is a necessary evil. Justify the statement. Discuss the significance of transpiration.

Q. Choose the correct answers from the alternatives given.
According to transpiration pull-cohesion theory of ascent of sap, water is pulled upward through the xylem. The cause of the pull is

1. Transpiration
2. Guttation
3. Root pressure
4. Condensation

Q. Theory of 'Ascent of Sap' was given by Dixon and Jolly. Which of them is against the theory?

1. Cohesive and adhesive properties of H${}_2$O
2. Requirement of ATP
3. Presence of pores in the tracheary elements
4. All of the above

Q. Water vapour comes out from the plant leaf through the stomatal opening. Through the same stomatal opening carbon dioxide diffuses into the plant during photosynthesis. Reason out the above statements using one of following options:

1. Both processes cannot happen simultaneously
2. Both processes can happen together because the diffusion coefficient of water and CO2 is different
3. The above processes happen only during night time
4. One process occurs during day time, and the other at night

Q. Transpiration is helpful to plants in _____.

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

Q. Perspiration and transpiration help to cool the body temperature of the organism. Give suitable explanation

Q. Which of the following is not a function of transpiration?

1. Uptake of water
2. Evaporation of water
3. Uptake of minerals
4. Excretion of minerals

Q. Water vapour comes out from the planet leaf through the stomatal opening. Through the same stomatal opening carbon dioxide diffuses into the plant during photosynthesis. Reason out the above statements using one of following option : -

1. Both processes cannot happen simultaneously.
2. Both processes can happen together because the diffusion coefficient of water and ${CO}_2$ is different.
3. The above processes happen only during night time.
4. One process occurs during day time, and the other at night.

Q.

Name the process/term for the statements given below:

Special pore-bearing structures are present on the margins of leaf to allow exudation.

Q. If transpiration doesn't take place in plants, which process will also not occur?

1. Respiration
2. Reproduction
3. Water transporation
4. Photosynthesis

Q. Who had said that ''transpiration is a necessary evil''?

1. Curtis
2. Andersen
3. J.C. Bose
4. Steward