Question

Mechanism of opening and closing of stomata

Answer 1

Answer:

The mechanism of the closing and opening of the stomata depends upon the presence of sugar and starch in the guard cells. ... Due to higher concentration of the cytoplasm of guard cells, the water comes to them from the neighbouring cells by osmosis and they become turgid. With the result the stomata remain open.

Explanation:

Answer 2

Explanation:

The mechanism of the closing and opening of the stomata depends upon the presence of sugar and starch in the guard cells. ... Due to higher concentration of the cytoplasm of guard cells, the water comes to them from the neighbouring cells by osmosis and they become turgid. With the result the stomata remain open.

The guard cells are always living and contain chloroplasts. These cells, however, contain much amount of protoplasm than the other ordinary cells. Usually the stomata are found scattered on the dicotyledonous leaves whereas they are arranged in parallel rows in the case of monocotyledonous leaves. The number of stomata may range from thousands to lacs per square centimeter on the surface of the leaf.

The stomata may be found on both the surfaces of the leaf, but their number is always greater on the lower surface. However, the upper surface of the leaves of banyan and rubber trees lack stomata. The upper surface of the leaves of several xerophytes also lacks the stomata.