What biological process allows plants to convert stored food reserves into useful energy?

The correct choice is respiration, which is a critical biological process that enables plants to convert stored food reserves into energy. During respiration, plants break down glucose, which is derived from the food they have stored, often in the form of starch. This process occurs in the mitochondria of plant cells and involves the utilization of oxygen to convert glucose into adenosine triphosphate (ATP), the energy currency of cells.

In this way, respiration allows plants to access energy from their food reserves to support their growth, metabolism, and various physiological functions. Unlike photosynthesis, which primarily involves the production of glucose using sunlight, respiration is the process that utilizes that stored glucose to generate energy, essential for plant survival and development.

Fertilization refers to the union of male and female gametes, and transpiration involves the movement of water through a plant from the roots to the leaves, which are unrelated to the energy conversion process.