Biosphere is a special Earth cover, where activity of all living organisms and cycle of matter and energy between them is realized actively. It is a«vital cover» of the Earth. It includes the bottom of atmosphere, hydrosphere and upper lithosphere. There is no a general opinion among scientists about upper and bottom biosphere borders. Living organisms are very closely located in the bottom atmosphere, especially up to 100 meters. Nowadays, taking into account living organisms’ spreading, upper bound of biosphere is drawn along the ozone layer (25-30 km); lower bound is drawn along the bottom of the World Oceandeepest channel. There are such chemical elements as: hydrogen, carbon, oxygen, nitrogen, phosphorus, silicon in the organic world structure. Such elements are called biophylicelements, atoms of which form complex molecules of the living organisms.
Living organisms, forming biosphere, are divided to 2 big groups: flora (plants) and fauna (animals). The Earth total weight less than The Earth total mass in many times. Biomass size on the continents is more than in the World Ocean in 800 times. There are green plants on the continents; there are animals in oceans.
Living organisms carry out cycle of the biological matter and energy in the Earth. This process, which is the main factor of the organic world, is realized in 3 stages. First of all, during photosynthesis, which takes place with the help of the solar energy, primary organic matters are formed and oxygen is isolated. On the second stage primary organic products turn into products of animal kind. On the last stage organic matters disintegrate. Living organisms that take part in such periods of the biological cycle are divided into 3 groups: