Role of Stomata in Minimizing Photorespiration

Q. Closed stomata reduces

1. Rate of transpiration
2. Amount of carbon dioxide entering the leaf
3. Both rate of transpiration and amount of carbon dioxide entering the leaf
4. Rate of respiration

Q. Stomata opens during the day and closes during the night because

1. Enzymes convert starch into sugar during the night
2. None of the above
3. Formation of sugar increases osmotic concentration of cell sap which results in absorption of water which provide turgidity to guard cells
4. Photosynthesis takes place during daytime only

Q.

C4 plants, by decreasing photorespiration and efficiently carrying out photosynthesis, can?

1. Decrease stomatal openings and thereby reduce water loss.

2. Decrease stomatal openings and thereby reduce leaf temperature.

3. Increase stomatal openings and thereby increase water loss.

4. Increase stomatal openings and thereby increase leaf temperature.

Q. Leaves that appear wilted during the daytime recovers at night because

1. stomata closes during night, temperature decreases, transpiration is reduced and plant is able to absorb more water from the soil
2. transportation of organic substances increase during night
3. All of the above
4. light is essential for photosynthesis

Q. Which is not true regarding stomata?

1. They are turgor operated valves
2. Have differentially thickened walls of guard cells
3. They close when guard cells are turgid
4. Show scotoactive opening in CAM plants

Q. Closed stomata reduces

1. Rate of transpiration
2. Amount of carbon dioxide entering the leaf
3. Rate of respiration
4. Both rate of transpiration and amount of carbon dioxide entering the leaf

Q.

C4 plants, by decreasing photorespiration and efficiently carrying out photosynthesis, can?

1. Decrease stomatal openings and thereby reduce water loss.

2. Decrease stomatal openings and thereby reduce leaf temperature.

3. Increase stomatal openings and thereby increase water loss.

4. Increase stomatal openings and thereby increase leaf temperature.

Q. Stomata opens during the day and closes during the night because

1. Enzymes convert starch into sugar during the night
2. Photosynthesis takes place during daytime only
3. Formation of sugar increases osmotic concentration of cell sap which results in absorption of water which provide turgidity to guard cells
4. None of the above

Q. Leaves that appear wilted during the daytime recovers at night because

1. light is essential for photosynthesis
2. stomata closes during night, temperature decreases, transpiration is reduced and plant is able to absorb more water from the soil
3. transportation of organic substances increase during night
4. All of the above

Q.

C4 plants, by decreasing photorespiration and efficiently carrying out photosynthesis, can?

1. Decrease stomatal openings and thereby reduce water loss.

2. Decrease stomatal openings and thereby reduce leaf temperature.

3. Increase stomatal openings and thereby increase water loss.

4. Increase stomatal openings and thereby increase leaf temperature.