Question

plants also perform cellular respiration. why do plants need this process even though they can make food through photosynthesis?

Explanation:

Photosynthesis produces glucose and oxygen. Cellular respiration breaks down glucose to release energy (ATP) that plants need for various life - processes like growth, transport, and reproduction. During night or in low - light conditions when photosynthesis is not occurring, respiration provides the necessary energy.

Answer:

Plants need cellular respiration to release energy (ATP) for their life - processes. Photosynthesis only makes food, and respiration is required to convert the stored energy in glucose into usable energy. Also, when photosynthesis is not possible (e.g., at night), respiration provides the energy needed to sustain the plant.