§ 51. Human life (textbook)

§ 51. Human life


Remember that age of the earth.


Composition biosphere. Our Planet exists in the infinite space of the universe, with thin air cover, which does not evaporate the water and oxygen disappear. This Land - the only all known planets, which is an environment where there is life - biosphere.

Born Life on Earth 3,5 billion years ago. The first primitive creatures were bacteria - microorganisms. They emerged in shallow waters in warm and humid climate. Much later algae appeared - the first plants on earth. Millions of years passed before in ancient seas emerged first animal. From the water of life and has spread on land. Throughout geologic history of the development of organisms was walking unevenly. Some species remained almost unchanged from the ancient geological eras to the present time. Development second led to complex forms of life up to man. And the Third ended with extinction, such as dinosaurs.

Now in the biosphere, comprising about 2 million species organisms. They are very diverse. You know Plants: Algae, grass, bushes, trees. You know Animals: Worms, snakes, frogs, fish, insects, birds, mammals (animals). There are also many kinds of MicroorganismsI have not just discernible even under a microscope. Separately, in the nature of produce mushrooms.

The relationship between organisms. Plants, animals and microorganisms may exist only in close connection with each other. Only plants are capable of photosynthesis from lifeless - inorganic chemicals to create living - organic, while highlighting oxygen. For this they called the "oxygen factories. Animals can not themselves create organic matter, but to live without them can. Because they feed on plants (herbivores) or eat each other (Predators). Animals inhale oxygen and exhale carbon dioxide, which is necessary plants for photosynthesis. The remains of plants and animals have long covered the entire Earth layer a few tens of meters, if not microscopic. They decompose them inorganic substances, and they again become suitable for power plants. In this biological cycle all levels: plants, animals, microorganisms - are interrelated.

The limits of the biosphere. The originality of the biosphere is fatigue that it  placed in other shells: atmosphere, lithosphere, hydrosphere. Ceiling biosphere is in atmosphere at altitudes of 20-30 km - altitude of the ozone layer that protects all life from harmful action of ultraviolet radiation. Ground-air space - habitats of birds and the upper limits of life scattered in the troposphere as microorganisms and pollen plants. In the hydrosphere beings are in all layers water. Lower limit place in the biosphere lithosphere at a depth of about 5 km, where at high temperature layers of earth crust and the absence of oxygen There may be again only microorganisms.

Despite to such a wide margin the biosphere, most organisms on Earth exists in a thin layer - the region of interaction of air, water and rocks on Earth surface - the band most close contact of the atmosphere, lithosphere and hydrosphere. This layer, which concentrated all life, figuratively called the "tape of life".

Interaction with other shell of the biosphere of the Earth. Activities of living organisms affected all environments of the Earth. The influence of organisms on atmosphereassociated with photosynthesis. Plants absorb carbon dioxide and emit oxygen. Animals, by contrast, absorb oxygen and exhale carbon dioxide. This way organisms regulate the content of these gases in the atmosphere.

Organisms affect hydrosphere. They take the water of seas and oceans, they need substances (especially calcium) to build their skeletons, armor, shells. Because salt is excessively accumulated in the water and not zasolyuyetsya Ocean.

Impact organisms on lithosphere known to you. From their mountain remnants formed species of organic origin (limestone, peat, coal) and some form surface (coral plant). On the other side of the mountain destroying organisms rocks (organic weathering).


FAQ task

1. Name the components of the biosphere.

2. Where are the boundaries of the biosphere?

3. How do organisms interact?

4. How do organisms affect the environment?

5. Can organisms affect the lithosphere? How?

6. Why do animals, plants and microorganisms can not exist separately other?