Green plants absorb light energy using chlorophyll in their leaves. They use it to react carbon dioxide with water to make a sugar called glucose. The glucose is used in respiration, or converted into starch and stored. Oxygen is produced as a by-product. This process is called photosynthesis. Temperature, carbon dioxide concentration and light intensity are factors that can limit the rate of photosynthesis. Photosynthesis summary
Photosynthesis [photosynthesis: The chemical change that occurs in the leaves of green plants. It uses light energy to convert carbon dioxide and water into glucose. Oxygen is produced as a by-product of photosynthesis. ] is the chemical change which happens in the leaves of green plants. It is the first step towards making food - not just for plants but ultimately every animal on the planet. During photosynthesis:
* Light energy is absorbed by chlorophyll, a green substance found in chloroplasts in some plant cells and algae * Absorbed light energy is used to convert carbon dioxide (from the air) and water (from the soil) into a sugar called glucose * Oxygen is released as a by-product
This equation summarises what happens in photosynthesis:
Some glucose is used for respirationrespiration: Chemical change that takes place inside living cells, which uses glucose and oxygen to produce the energy organisms need to live. Carbon dioxide is a by-product of respiration, while some is converted into insoluble starchstarch: A type of carbohydrate. Plants can turn the glucose produced in photosynthesis into starch for storage, and turn it back into glucose when it is needed for respiration. for storage. The stored starch can later be turned back into glucose and used in respiration. Factors limiting photosynthesis
Three factors can limit the speed of photosynthesis: light intensity, carbon dioxide concentration and temperature. *
Without enough light, a plant cannot photosynthesise very...