The process that allows for the exchange of gases in plant leaves is called photosynthesis and involves the opening of small pores known as stomata. Through these stomata, plants take in carbon dioxide from the atmosphere and release oxygen as a by-product. This gas exchange is essential for the plant's ability to convert light energy into chemical energy stored in glucose. The regulation of stomatal openings is influenced by various factors, including light intensity, humidity, and the plant’s physiological state, critical for maintaining overall plant health.