Final answer:
Leaves are involved in cellular respiration as well as photosynthesis, with mitochondria in the leaves engaging in the continuous process of converting glucose into energy (ATP), which necessitates the uptake of oxygen and the release of carbon dioxide.
Step-by-step explanation:
Cellular respiration can be observed in leaves, indicating that they do not only partake in photosynthesis but also in cellular respiration. While it is generally known that leaves are involved in photosynthesis due to the presence of chlorophyll and the production of oxygen and glucose, the continuous process of cellular respiration is sometimes overlooked. However, leaves also contain mitochondria where cellular respiration takes place. This process uses the glucose produced during photosynthesis to generate ATP.
The gas exchange observed through stomata in leaves, where carbon dioxide is absorbed, and oxygen is released, is part of photosynthesis during the day. Concurrently, cellular respiration occurs when oxygen enters the leaf's cells to be used for breaking down glucose, resulting in the production of carbon dioxide, water, and energy in the form of ATP. This process occurs continuously, both day and night.
Direct evidence of cellular respiration in leaves can be obtained by measuring the uptake of oxygen and the release of carbon dioxide, which can be tracked using various scientific methods. This activity confirms that photosynthesis and respiration are interconnected cycles that occur in plants and are essential for their survival.