The Biosphere includes all living organisms on earth and all of the organic matter that they produce. All ecosystems and habitats are a part of the biosphere.
All organisms making up the biosphere rely on photosynthesis to produce energy. Photosynthesis supports the biosphere by using sunlight in order to produce nutrients that can be used by living things.
Earth's living organisms rely on the atmosphere for oxygen and to shield them from ultraviolet radiation. Organisms on earth have evolved to survive in very specific atmospheric conditions. Air in the atmosphere is made up of several gases.
Gases in the atmosphere:
.9% argon
78% nitrogen
21% oxygen
.037% carbon dioxide