B5 - Photosynthesis

The process by which plants synthesise carbohydrates from raw materials using energy from light

Photosynthesis is a chemical reaction

Atoms in the reactants are rearranged to make the products

carbon dioxide + water → glucose + oxygen

6Co₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

Carbon dioxide and water react together to make glucose and oxygen but they only do that in the presence of sunlight and chlorophyll.

Energy transfer in Photosynthesis

• CO₂ from the atmosphere is diffused into the leaves

• Water is absorbed from the soil by root hair cells and transported to leaves in xylem vessels

Chlorophyll

Green pigment (coloured substance) in

Products of Photosynthesis

Oxygen is released into the atmosphere (or water if plants/algae are aquatic)

Glucose is the starting material for a plant to make all the nutriens