Question

Which out of the following is a mismatched pair?
A. Hypostomatic-stomata present more on lower epidermis than on upper epidermis
B. Epistomatic- stomata present more on upper epidermis only
C. Amphistomatic- stomata nonfunctional or absent
D. Sunken stomata- stomata deep-seated below the surface

Answer 1

The epidermis of leaves has small openings called stomata through which gas exchange. The stomata can be seen as small pores mainly found on the underside of the leaf.

Complete answer:
Stomata are the small openings present on the inner surface of the leaves. They are bounded by the two guard cells. Stomata can be opened or closed depending on the turgidity of guard cells. The closing and opening of the stomata depend upon the concentration of carbon dioxide in the air. Let us analyze each given option to find out the correct answer.

Option A: In hypostomatic leaf, stomata present more on the lower epidermis than on the upper epidermis. A leaf is said to be hypostomatic when the stomata are present on the underside of the leaf. Thus, this is the correct match. Therefore, this is an incorrect option.

Option B: In the epistomatic leaf, the stomata present are more on the upper epidermis only. Such type of leaf is found in aquatic plants where the leaves float on the surface of the water, e.g. Nymphaea. Thus, this is the correct match. Therefore, this is an incorrect option.

Option C: The amphistomatic leaf has stomata that are present on both adaxial and abaxial surfaces. The abaxial surface contains more number of stoma in comparison to the adaxial surface. Most plants of herbaceous dicotyledonous possess such leaves. Thus, this is an incorrect match. Therefore, this is the correct option.

Option D: Sunken stomata is a stoma present in a small pit that prevents water loss, decreasing water loss from the leaf. Thus, this is the correct match. Therefore, this is an incorrect option.

Thus, the correct option is option C. Amphistomatic- stomata nonfunctional or absent.

Note: Some of the main functions of stomata are as follows:
I. It opens and closes the pores in the leaves for an exchange of gases.
II. It allows the plant to take in carbon dioxide and give out oxygen for photosynthesis.
III. Depending on the weather conditions, it closes or opens its pores to keep the moisture content developed.