Photosynthetic Reaction (AQA GCSE Biology: Combined Science)

• Plants are autotrophs – this means that they can make their own food using light, water and carbon dioxide
• This is why they are called producers in food chains
• Photosynthesis is an endothermic reaction in which energy is transferred from the environment to the chloroplasts by light
  • The leaves of the plant are where most photosynthesis takes place, in specialised mesophyll cells which are packed with chloroplasts containing chlorophyll to absorb as much light energy as possible

• The sugars produced by photosynthesis are used to make all the substances a plant needs, as well as being used in respiration to release energy
• These reactions can be summarised into a simple equation

 

Word equation for photosynthesis

 

Balanced symbol equation for photosynthesis

• The reactants for photosynthesis are obtained by a plant as follows:

 

Plants obtain the materials they need for photosynthesis from the environment