What is the function of stomata in plants?

Stomata are small openings found on the surfaces of plant leaves and stems that play a critical role in gas exchange. Their primary function is to facilitate the movement of gases in and out of the plant, specifically allowing for the uptake of carbon dioxide needed for photosynthesis and the release of oxygen as a byproduct.

These openings also enable the plant to regulate transpiration, which is the loss of water vapor from inside the leaf to the atmosphere. By opening and closing, stomata help maintain the balance between the need for carbon dioxide and the need to conserve water, particularly in varying environmental conditions. This regulation is vital for the plant's overall health and efficiency in carrying out photosynthesis.

In contrast, while nutrient absorption typically occurs through roots, water storage relates more to the plant's internal structures and not directly through stomata. Photorespiration is a separate process that may occur at stomata but is not their primary function. Therefore, the focus of stomata is predominantly on gas exchange, making it the correct answer.