What Are the Important Functions of Leaves?

Photosynthesis

• Photosynthesis is the most important and primary function of all leaves. Photosynthesis is a process whereby plant and tree leaves create sugar from water, carbon dioxide and sunlight. Sunlight shines on leaves and is trapped by chlorophyll in chloroplasts. Water is used to change the energy from light into a chemical energy, and the energy is then stored. Stored chemical energy is then used to make food, which is carried to all the other parts of the plant or tree.

Oxygen

• Leaves are necessary for a plant to live, and plants are necessary for people to live. Plants create the oxygen that people breath and also control the carbon dioxide, through the process of photosynthesis. Carbon dioxide is absorbed into leaves, since plants need carbon dioxide as a part of photosynthesis. As a leaf produces food necessary for the survival of the plant, oxygen is created at the same time and released into the air for people to breath.

Cellular Respiration

• Cellular respiration is a process in which cells of a leaf convert biochemical energy from nutrients into adenosine triphosphate. Waste products are then released. Some of the nutrients that are used by leaves during cellular respiration include fatty acids, amino acids, sugar and molecular oxygen. Energy produced during this process is used for the various parts of the plant, such as the roots, tree trunk, limbs, buds and flowers.

Dead Leaves

• Most do not think of dead leaves as having a function. Normally, as leaves begin to fall they are thought of as a nuisance since they have to be raked and removed. Dead plants and leaves do have an important function though, as organic matter that fertilizes soil. The nitrogen cycle uses dead leaves and plants that have been decomposed to benefit living plants. In some cases, dead leaves fall off the plant and are even used as insulation to protect the plant.