An Opening in Leaves That Functions in the Exchange of Gases

Question

An opening in leaves that functions in the exchange of gases is called a ____.  
A) cuticle
B) stoma
C) guard cell
D) pit
E) pore

Accepted Answer

Stoma (also known as stomata) is the opening in leaves that allows for the exchange of gases, including oxygen and carbon dioxide, with the environment. It is surrounded by two specialized cells called guard cells, and together they regulate the opening and closing of the stoma to control gas exchange and water loss. The cuticle is a waxy layer on the surface of leaves that helps prevent water loss, while pit refers to a small indentation or depression and is not specifically related to gas exchange. Pore is a general term for any small opening, but stoma is the specific term for the opening in leaves.