Which process allows plants to make their own food and convert it to energy?

Photosynthesis is the process through which plants convert light energy, typically from the sun, into chemical energy in the form of glucose. During photosynthesis, plants take in carbon dioxide from the air and water from the soil. Chlorophyll, the green pigment found in plant leaves, captures sunlight, which drives the chemical reactions that convert these raw materials into glucose and oxygen. This glucose serves not only as food for the plant, providing the energy and building blocks necessary for growth and development, but is also essential for cellular respiration, where the energy stored in glucose is further converted into a form that can be used by the plant for various metabolic processes.

This ability to produce their own food through photosynthesis is what distinguishes plants from consumers. The other options refer to processes that are related to plant function but do not involve the direct conversion of light into food. The nitrogen cycle pertains to the transformation of nitrogen in various forms for use by plants; respiration involves the process of breaking down glucose for energy, and phototropism is the growth response of plants to light direction rather than the conversion of light into food.