Summary Word Equation

Water + Carbon Dioxide (in the presence of light and chlorophyll) –> Glucose and Oxygen

Photosynthesis: a two-stage process:

Light reactions stage:

• The light energy from the sun is trapped by chlorophyll in the chloroplasts and is converted into chemical energy which is used to generate ATP.
• Water is split to produce hydrogen and oxygen.
• Oxygen diffuses from the cell.

Carbon fixation stage:

• A series of enzyme- controlled reactions
• which use hydrogen and ATP (produced by the light reactions)
• Combined with carbon dioxide
• to produce sugar (glucose)

Uses of sugar

• The chemical energy in sugar is available for respiration.
• Or the sugar can be converted into other substances, such as
  • starch (storage)
  • cellulose (structural).

Limiting factors

Limiting factors include:

• carbon dioxide concentration
• light intensity
• temperature

Their impact on photosynthesis and plant growth is displayed on the graphs.