Photosynthesis is process by plants and other autotrophs store the energy of sunlight into sugars.

Photosynthesis requires sunlight water and carbon dioxide.

The chemical equation for photosynthesis is:

6 CO2  +   6 H20   à   C6H12O6   +    6 O2

Photosynthesis occurs in the leaves of plants in organelles called chloroplasts.

Most photosynthesis occurs in the palisade layer of the leaf.

Gas exchange of CO2 and O2 occurs at openings called stomata surrounded by guard cells on the lower leaf surface.

Chlorophyll is the most important photosynthetic pigment.

These pigments are embedded in the membranes of the chloroplast in groups called photosystems.

Photosynthesis occurs in two main phases:

1. Light phase: Light is absorbed by pigments.

1. Light and water are required.
2. Energy storage molecules are formed.
3. Oxygen gas is made as a waste product.
   

1. Dark phase: Trapped energy from the sun is converted to the chemical energy of sugars.
1. Carbon Dioxide is fixed into the sugar glucose.
2. Molecules created during the light phase power the production of this glucose.