How do living organisms change the Atmosphere?

Question

How do living organisms change the Atmosphere?

Answer 1

it si probable that the oxygen in our atmosphere came from millions of years of stromatolites giving it off as a waste product. respiring biota give off carbon dioxide (inlcuding plants). Farting biota (via bacterial fermentation) give off methane, indole and skatole and various other sulphurous compounds. Plants give off oxygen via phtotsynthesis. Certain bacteria fix nitrogen from the atmosphere into plant-available forms. Theoretically a rise in CO2 from human activities could be offset by increasedf plant phtosynthesis; eg from algal blooms or increased forestry planting.

Answer 2

That easy, Plants absorb the carbon dioxide exhaled by animals, Animals inhale the oxygen that is released by plants, all this is changing the atmosphere to an extent. This gas exchange helps keep the atmosphere in balance. Another example would be the nitrogen, carbon and phosphorous cycle that occurs in nature. The decomposition of dead plant and animal life help refill the atmosphere with these gases.