What is the primary function of leaves in a plant?

The primary function of leaves in a plant is photosynthesis, which is the process by which plants convert light energy, usually from the sun, into chemical energy stored in glucose. This process occurs mainly in the chloroplasts of leaf cells, where chlorophyll captures sunlight. Through photosynthesis, plants take in carbon dioxide from the atmosphere and water from the soil, using energy from sunlight to transform these substances into glucose and oxygen. This not only provides energy for the plant's growth and development but also is crucial for the entire ecosystem, as it produces oxygen that is vital for most life forms on Earth.

While leaves do play a role in other functions, such as influencing gas exchange and transpiration, their primary role is to facilitate photosynthesis, which is essential for the plant's energy production and sustenance.