Photosynthesis: How Plants Make Food

What is Photosynthesis?

Photosynthesis is the process by which green plants make their own food using sunlight. It takes place mainly in the leaves, inside the chloroplasts that contain the green pigment chlorophyll.

The Word Equation

Carbon dioxide + Water → (sunlight, chlorophyll) → Glucose + Oxygen

Requirements

• Sunlight provides energy.
• Chlorophyll traps light energy.
• Carbon dioxide enters through tiny pores called stomata.
• Water is absorbed by the roots.

Why it Matters

• It produces the oxygen we breathe.
• It is the starting point of almost every food chain.
• It removes carbon dioxide from the air.

Key Points

Photosynthesis happens only in the presence of light, while respiration happens all the time. Both processes together keep life on Earth in balance.