Photosynthesis and cellular respiration are closely related biological processes that form a cycle essential for life.

• Photosynthesis occurs in plants and some other organisms, where light energy is used to convert carbon dioxide (CO₂) and water (H₂O) into glucose (C₆H₁₂O₆) and oxygen (O₂). The glucose serves as food and energy storage for the plant, while oxygen is released as a byproduct

• Cellular respiration takes place in the mitochondria of cells in plants, animals, and other organisms. It uses oxygen and glucose to produce energy in the form of ATP, releasing carbon dioxide and water as byproducts

The two processes are essentially opposite reactions:

Process| Reactants| Products
---|---|---
Photosynthesis| Carbon dioxide + Water + Light energy| Glucose + Oxygen
Cellular respiration| Glucose + Oxygen| Carbon dioxide + Water + ATP

• The oxygen produced in photosynthesis is the oxygen used in cellular respiration.
• The carbon dioxide produced in cellular respiration is the carbon dioxide used in photosynthesis

This reciprocal relationship helps maintain stable levels of oxygen and carbon dioxide in the atmosphere and is a key part of the carbon cycle

. In summary, photosynthesis stores energy by creating glucose and oxygen, while cellular respiration releases energy by breaking down glucose with oxygen to produce ATP, carbon dioxide, and water. Together, they form a biological energy cycle vital for life on Earth