THE OXYGEN-CARBON DIOXIDE CYCLE.
Oxygen-Carbon Dioxide Cycle Both are GASSES important to all living things. Unlike water which always stays water, oxygen (O 2 ) and carbon dioxide (CO 2 ) convert back and forth as they cycle on the planet.
ANIMAL CONTRIBUTION During respiration (breathing), animals inhale oxygen (O 2 ) and convert it to carbon dioxide (CO 2 ).
PLANT CONTRIBUTION During photosynthesis (the process where plants make food for themselves) plants breathe in carbon dioxide (CO 2 ) and exhale oxygen (O 2 ).
DECOMPOSERS Dead organic material contains carbon dioxide (CO 2 ), so as decomposers break down the tissue, carbon dioxide is released into the atmosphere.
FOSSIL FUELS Oil, Gas, Coal are examples. When these fuels are burned, they release carbon dioxide (CO 2 ) and water (H 2 O) into the atmosphere.