What is the main purpose of photosynthesis in plants?

The main purpose of photosynthesis in plants is to produce glucose and oxygen from carbon dioxide and water. This process occurs primarily in the chloroplasts of plant cells, where chlorophyll captures sunlight. The energy from sunlight drives a series of chemical reactions that convert carbon dioxide from the air and water absorbed by the roots into glucose, a simple sugar that serves as an energy source for the plant. Oxygen is released as a byproduct of this reaction.

This process is critical not just for plants, but for all living organisms on Earth, as it forms the base of the food chain. The glucose produced is essential for plant growth and energy, while the oxygen released contributes to the atmosphere, supporting aerobic life forms.

In contrast, converting sunlight into heat doesn’t represent the essential function of photosynthesis nor does it contribute to the plant's energy needs. While plants do absorb nutrients from the soil, this process is not the primary purpose of photosynthesis. Likewise, while plants do eliminate waste products, these activities are separate from the fundamental process of photosynthesis itself.