Why does carbon move easily through the atmosphere?

In the atmosphere, carbon is attached to oxygen in a gas called carbon dioxide (CO2). With the help of the Sun, through the process of photosynthesis, carbondioxide is pulled from the air to make plant food from carbon. Through food chains, the carbon that is in plants moves to the animals that eat them.

Learn More At: http://www.windows2universe.org/earth/Water/co2_cycle.html