photosynthesis

• Photosynthesis


  A chemical reaction which takes place in plants, converting carbon dioxide and water into glucose and oxygen using light energy
• Photosynthesis


  • Uses light energy to power the chemical reaction
  • Absorbed by the green pigment chlorophyll
  • An example of an endothermic reaction
  • Takes place inside the chloroplasts which are small organelles found in plant cells
• Photosynthesis


  1. Plants acquire carbon dioxide via diffusion

  2. Plants absorb water from the soil through the roots and transported to the cells carrying out photosynthesis, via the xylem

  3. 6CO2 + 6H2O + Light -> C6H12O6 + 6O2
• Glucose


  Made in photosynthesis, used for respiration, stored as starch, fat or oils, used to produce cellulose or used to produce amino acids for protein synthesis
• Limiting factor


  Something which stops the photosynthesis reaction from occurring at a faster rate
• Limiting factors


  • Temperature
  • Light intensity
  • Carbon dioxide level
• Increasing temperature


  Increases the rate of reaction up to around 45°C, then the enzymes become denatured
• Increasing light intensity


  Increases the rate of reaction because there is more energy to carry out more reactions
• Increasing carbon dioxide concentration

  Increases the rate of reaction because there are more reactants available