It is reasonably likely that you have some carbon atoms in your body that were once inside Charles Darwin or Marie Curie or any other long dead individual. Atoms exist in different forms or compounds at different times in history and cycle between them.
Carbon is an essential element for life on Earth and parts of the cells in our bodies, including carbohydrates, proteins, lipids and DNA, are made from it. The carbon cycle shows how atoms of this element can exist within different compounds, at different times.
Stage one of the carbon cycle
The carbon cycle is easiest to understand in terms of its processes and the conversion of carbon that they undertake. The three key processes and their conversions are shown in the table below.
|Process||Carbon starts as||Carbon ends as|
|Combustion (burning)||Fuel (eg methane or wood)||Carbon dioxide|