Photosynthesis

Plants, unlike animals, can make their own food. They do this using a process called photosynthesis.

The word and symbol equations for photosynthesis are:

Diagram illustrating the word and symbol equations for photosynthesis

Photosynthesis requires energy in the form of light to drive the chemical reaction. Photosynthesis is therefore an endothermic reaction.

The light energy required is absorbed by a green pigment called chlorophyll in the leaves. Chlorophyll is located in chloroplasts in plant cells, particularly the palisade mesophyll cells of the leaf.

The carbon dioxide required for photosynthesis comes from the air. It enters leaves through the stomata. These tiny pores are found mainly on the bottom of leaves. Water enters the plant through the roots and is transported to the leaves in the xylem vessels.

Biosynthesis

Some of the glucose produced by photosynthesis is used for respiration.

Glucose is the starting point for the synthesis of materials that plants need to live.

The glucose not used for respiration is used in the following ways:

An image showing the cycle of gluecose.