Photosynthesis

• Photosynthesis occurs in the chloroplasts in the leaves of a plant.
• The green pigment in leaves is called chlorophyll.
• Photosynthesis is an endothermic reaction.
• Light energy is used in photosynthesis.
• The word equation for photosynthesis is:

  Carbon Dioxide + Water -> Glucose + Oxygen
• The balanced symbol equation for photosynthesis is:

  6CO2 + 6H2O + C6H12O6 + 6O2
• A limiting factor is anything that limits the rate of reaction when it is in short supply
• The limiting factors of photosynthesis are:

  • Temperature.
  • Carbon dioxide concentration.
  • Light intensity.
  • Amount of chlorophyll.
• Light intensity affects the rate of photosynthesis as increasing light intensity increases the rate of photosynthesis until another factor becomes limiting.
• Carbon dioxide concentration affects photosynthesis as increasing carbon dioxide concentration increases the rate of photosynthesis until another factor becomes limiting.
• Increasing temperature increases the rate of photosynthesis as the reaction rate increases - at high temperatures enzymes are denatured so the rate of photosynthesis quickly decreases.
• The inverse square law for light intensity is : light intensity = distance^-2
• Limiting factors are important for economics of growing plants in greenhouses because greenhouses need to produce the maximum rate of photosynthesis while making profit.
• Plants use glucose for:

  • Respiration.
  • Convert it into insoluble starch for storage.
  • Produce fat or oil for storage.
  • Produce cellulose to strengthen cell walls.
  • Produce amino acids for protein synthesis.