Factors That Affect Photosynthesis

• • If plants have less chlorophyll they cannot carry out as much photosynthesis
  • the levels can vary due to disease, environmental stress, and lack of nutrients. (this all damages the chloroplasts)
• • As light intensity increases, so does photosynthesis.
  • BUT only to a certain point. Once the line plateaus it means there must be something else limiting photosynthesis.

  
• • As levels of carbon dioxide increase so does photosynthesis
  • after a while it plateaus.
  • meaning something else is the limiting factor.

  
• • Photosynthesis increases with temperature to a certain point as the enzymes are able to work more quickly
  • However, after reaching the optimum temperatures the enzymes become denatured and the rate will drop

  
• • Sometimes more than one limiting factor is shown on a graph, they may have been performed at different temperatures.
  • If we see a change in the graph, we know that temperature is the limiting factor.

  
• In colder climates farmers put their crops in greenhouses to keep them at the optimum temperature
• greenhouses trap the suns heat
• greenhouses can provide artificial light so that photosynthesis can happen at day and night.
• farmers may pump carbon dioxide into the greenhouse or use a paraffin heater
• paraffin heaters release heat and carbon dioxide
• greenhouses are closed so that pests and pathogens can't affect the plants
• fertilisers give the plant enough minerals
• pesticides kill any unwanted bugs
• farmers weigh up the costs of aiding photosynthesis to the extra yield it will bring them