Question

Assertion (A): Most of the plants close their stomata at night.

Reason (R): Closing of stomata helps to conserve water as large amount of water evaporates from the leaves.

Options

• Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).

• Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).

• Assertion (A) is true, but Reason (R) is false.

• Assertion (A) is false, but Reason (R) is true.

Answer 1

Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).

Explanation:

Both assertion and reason are true as Plants close their stomata at night to conserve water. During the day, stomata open for photosynthesis, allowing gas exchange. At night, when photosynthesis ceases, plants close these pores to prevent water loss through evaporation. The opening and closing are controlled by guard cells, conserving water while not needing CO₂ for photosynthesis​.