The process of cellular respiration, carried out by all living organisms, involves the catabolic break down and conversion of carbon containing molecules especially glucose (6-carbon) into ATP and energy yielding compounds such as NADH and FADH2. This energy helps drive cellular processes for daily bodily functions.
C6H12O6 + 6O2 --> 6CO2 + 6H2O + ATP
Decomposition involves the conversion of living matter into simpler compounds by the action of special organisms called decomposers. This group principally includes bacteria and fungi. Bacteria and fungi degrade matter with the help of their enzymes and release nutrients into the soil. This process is a rich carbon and nutrient source for the plants and other soil borne organisms.
Fossilization is the process of preservation of living organisms in the form of rocks or sediments. Over millions of years and under intense pressure and temperature, these remains are converted into rich carbon sources such as coal, natural gas and oil. Therefore, this process converts carbon in the living system to fossil fuels.
