What is the link between photosynthesis and transpiration?

Photosynthesis and transpiration are linked as both processes occur in plants and involve the exchange of gases.

Photosynthesis is the process by which green plants, algae and some bacteria convert light energy, usually from the sun, into chemical energy in the form of glucose. This process takes place in the chloroplasts, specifically using chlorophyll, the green pigment involved in light absorption. The general equation for photosynthesis is 6CO2 + 6H2O → C6H12O6 + 6O2. This means that carbon dioxide and water are used to produce glucose and oxygen.

Transpiration, on the other hand, is the process by which water is transported from the roots to the rest of the plant, including the leaves, where it is evaporated into the atmosphere through small openings called stomata. This process is primarily driven by the water potential gradient that exists between the plant and its surrounding environment.

The link between photosynthesis and transpiration is through the stomata. These tiny openings on the surface of leaves are where both the intake of carbon dioxide and the release of oxygen (for photosynthesis) and the evaporation of water (transpiration) occur. During the day, when photosynthesis occurs, the stomata open to allow the intake of carbon dioxide. This also allows water to escape, driving transpiration.

Furthermore, the water that is transported to the leaves during transpiration is also used in the photosynthesis process. The water molecules are split during the light-dependent reactions of photosynthesis, releasing oxygen as a by-product. Therefore, the processes of photosynthesis and transpiration are interconnected, with each process influencing and being influenced by the other.

In summary, photosynthesis and transpiration are two vital processes in plants that are closely linked. They both involve the exchange of gases through the stomata and the use of water, highlighting the intricate balance and interdependence of processes within plants.