When living organisms die, their bodies decompose and are broken down by bacteria and fungi. During this process, some of the carbon stored in the organism's tissues is released as carbon dioxide through respiration. This carbon dioxide can eventually be absorbed by water and form carbonic acid, which can react with minerals in rocks and form new compounds that incorporate the carbon. Over time, these compounds can become part of the rock structure, effectively transferring the carbon from the bodies of living organisms into the rocks.
