6. Photosynthesis

What you need to know...
  • What is photosynthesis?
  • What are the requirements for photosynthesis? 
  • What happens if any of the requirements for photosynthesis are in short supply?
  • How might be overcome limiting factors to photosynthesis?
What is photosynthesis?

What do we do when we are hungry? We might buy a snack, go to a cafe or look in the fridge for some food.
But what about plants, well they have a different plan! When they need food they can carry out a very clever process called photosynthesis!
So what is photosynthesis? Well again, the clue is in the name:
Photo (light) + synthesis (making) = making with light.
In photosynthesis, plants use the light energy from the sun to react water and carbon dioxide together to make food in the form of sugar. We can summarise this as a word equation:
 Limiting factors to photosynthesis
If any of the requirements (light, water, carbon dioxide or a suitable temperature) are low or missing, the photosynthesis rate is limited.

By overcoming these limitations, faster growth rates can be achieved.
  • Light - can be increased using artifical lights in greenhouses
  • Water - can be increased using an irrigation system.
  • Carbon dioxide - can be increased by burning a paraffin stove or getting extra supplies from a factory which produced carbon dioxide as a waste product.
  • Temperature - can be increased by using heaters in a greenhouse.