Final answer:
A stoma is an opening found on the surface of plant leaves that allows for the exchange of gases and water vapor with the external environment. It plays a crucial role in photosynthesis and helps regulate water loss through transpiration. Environmental cues influence the opening and closing of stomata to adapt to the plant's surroundings.
Step-by-step explanation:
A stoma (plural stomata) is an opening found on the surface of plant leaves that allows for the exchange of gases (carbon dioxide, oxygen) and water vapor with the external environment. Stomata are surrounded by specialized cells called guard cells, which control the opening and closing of the stomata.
Stomata play a crucial role in photosynthesis by allowing carbon dioxide to enter the leaf and oxygen to be released. They also regulate the transpiration of water vapor, helping to maintain a balance between efficient photosynthesis and water loss.
Environmental cues such as light intensity and quality, leaf water status, and carbon dioxide concentrations influence the opening and closing of stomata, ensuring that plants can adapt to their surroundings and optimize their gas exchange.