Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy from the sun into chemical energy stored in glucose. It occurs mainly in the chloroplasts of plant cells, which contain the green pigment chlorophyll. During photosynthesis, plants take in carbon dioxide (CO₂) from the air and water (H₂O) from the soil. Using sunlight as energy, these raw materials undergo a series of chemical reactions to produce glucose (C₆H₁₂O₆) and oxygen (O₂) as a byproduct. The overall equation for photosynthesis is:
6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂.
This process is essential not only for plant growth but also for maintaining atmospheric oxygen levels and providing energy to nearly all living organisms through the food chain.