The natural source of carbon dioxide that was left out is the calcareous shells of organisms. The major metabolic process that was left out is respiration.
Carbon dioxide is one of the gases that cycle around in the universe. It is an integral part of the carbon cycle. The carbon cycle is a model that depicts the movement of carbon in the ecosystem.
The natural source of carbon dioxide that was left out is the calcareous shells of organisms. The major metabolic process that was left out is respiration.
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