Carbon Cycle

1. Carbon enters the ecosystem through photosynthesis, they use carbon from CO2 to make carbohydrates, lipids and proteins

2. Animals then eat these plants which passes on the carbon compounds

3. Respiration by living plants and animals releases CO2 back to the atmosphere

4. Plants and animals will eventually die and decomposed, or are killed

5. When they decompose they are broken down by microorganisms like bacteria and fungi, which releases enzymes and catalyse the breakdown of dead material into smaller molecules

6. Decomposers will release CO2 back into the air by respiration as they break down the dead organism

7. Some useful plant and animal products like wood and fossil fuels are burned through combustion, which also releases CO2 into the air

8. Decomposition means that habitats can be maintained for the organisms still living, e.g when the nutrients of the dead are returned to the soil and waste materials don’t just pile up

Molecules in living things that are based on carbon

• Proteins

• Lipids

• Nucleic acids

• Carbohydrates

Respiration: Carbon in glucose is oxidised into Carbon in the air as CO2

Photosynthesis: Carbon in CO2 is fixed into sugars and other chemicals in plants

Combustion: When fuels are burned, CO2 is released into the air

Decomposition: When organisms or parts of organisms or waster decay/decompose, CO2 is released into the air

Fossilizations: When animals die, they decompose and the remains are stored in layers that eventually turn into rocks or minerals