What part of a plant cell controls gas exchange?

• A. Stomata
• B. Epidermis
• C. Chloroplasts
• D. Cuticle

Answer: (B)

The process of gas exchange in plants is primarily regulated by stomata, which are small openings on the surfaces of leaves and stems. These pores allow for the exchange of gases such as carbon dioxide, oxygen, and water vapor. Stomata open and close in response to environmental conditions, helping the plant manage water loss and facilitate the essential process of photosynthesis.

The epidermis covers the outer layer of the plant and does provide protection, but it is the stomata found within the epidermis that directly controls gas exchange. While chloroplasts are involved in the process of photosynthesis by capturing light energy, they do not play a role in regulating gas exchange. The cuticle, a waxy layer on the surface of leaves, helps to prevent water loss but does not regulate gas exchange directly. Hence, stomata are the correct answer to the question regarding the control of gas exchange in plant cells.