the process by which oxygenreleased into the atmosphere by photosynthetic organisms is taken up by aerobic organisms while the carbon dioxide released as a by-product of repiration is taken up for photosynthesis. Origin ofoxygen cycle Expand.
The oxygen cycle is the biogeochemical cycle ofoxygen within its three main reservoirs: the atmosphere (air), the total content of biological matter within the biosphere (the global sum of all ecosystems), and the Earth's crust.
