What is the process by which plants convert sunlight into energy?

The process by which plants convert sunlight into energy is known as photosynthesis. During photosynthesis, plants utilize sunlight, carbon dioxide from the air, and water from the soil to produce glucose and oxygen. This process primarily occurs in the chloroplasts of plant cells, where chlorophyll absorbs sunlight.

Photosynthesis is crucial for life on Earth because it is the foundation of the food chain; plants synthesize their own food and serve as a primary energy source for herbivores, which in turn are consumed by carnivores. The significance of this process extends beyond just energy creation, as it also contributes to the oxygen content in our atmosphere, supporting aerobic life.

The other options represent different biological processes. Respiration refers to how organisms break down glucose to release energy, transpiration involves the movement of water within plants and its evaporation from the leaves, and fermentation is a metabolic process that occurs in the absence of oxygen, typically in some microorganisms and under certain conditions. Thus, these processes do not directly relate to the conversion of sunlight into energy.