What is the process by which plants make food called?

Photosynthesis is the process by which plants create their own food using sunlight, carbon dioxide from the air, and water from the soil. This process occurs primarily in the leaves where chlorophyll captures light energy. During photosynthesis, the energy from sunlight is used to convert carbon dioxide and water into glucose, a type of sugar that serves as food for the plant. Oxygen is produced as a byproduct and released into the atmosphere.

In contrast, respiration refers to the process by which plants (and all living organisms) convert glucose into energy for cellular functions, but it is not how they create food. Transpiration involves the evaporation of water from plant leaves, which helps with nutrient transport and cooling but does not relate to food production. Digestion is the breakdown of food into simpler substances so that they can be absorbed, a process that pertains more to animals than to how plants generate their sustenance. Thus, photosynthesis stands out as the critical and defining process of food production in plants.