Download - UNIT 7 Energy changes the Earth Biology and Geology 3. Secondary Education THE LAYERS OF THE EARTH
UNIT
3
Biology and Geology 3. Secondary Education
UNIT
7The layers of the Earth
Geosphere
Biosphere Atmosphere
Hydrosphere
The Earth is composed of a series of layers, as shown in the illustration.
To know more about them, click on each one.
UNIT
3
Biology and Geology 3. Secondary Education
UNIT
7The layers of the Earth
The geosphere
• The geosphere is composed of the crust, the mantle and the core.
The crust is the outermost solid layer of the Earth. It is composed of rocks of low density.
The core is the innermost layer of the planet. Its density is high because it is composed of metals.
The mantle is an intermediate layer beneath the crust. It is composed of rocks which are slightly denser than those of the crust.
UNIT
3
Biology and Geology 3. Secondary Education
UNIT
7The layers of the Earth
Geosphere
Biosphere Atmosphere
Hydrosphere
The Earth is composed of a series of layers, as shown in the illustration.
To know more about them, click on each one.
UNIT
3
Biology and Geology 3. Secondary Education
UNIT
7The layers of the Earth
The hydrosphere
The hydrosphere is composed of all the water on Earth: the oceans, the seas, the ice in the glaciers, the lakes, the rivers, the streams, etc. This layer covers three quarters of the Earth’s surface.
UNIT
3
Biology and Geology 3. Secondary Education
UNIT
7The layers of the Earth
Geosphere
Biosphere Atmosphere
Hydrosphere
The Earth is composed of a series of layers, as shown in the illustration.
To know more about them, click on each one.
UNIT
3
Biology and Geology 3. Secondary Education
UNIT
7The layers of the Earth
The atmosphere
The atmosphere is the outermost and the lightest layer of the Earth. It is composed of all the gases that make up the air (78% nitrogen, 21% oxygen and small amounts of other gases, such as carbon dioxide and water vapour).
UNIT
3
Biology and Geology 3. Secondary Education
UNIT
7The layers of the Earth
Geosphere
Biosphere Atmosphere
Hydrosphere
The Earth is composed of a series of layers, as shown in the illustration.
To know more about them, click on each one.
UNIT
3
Biology and Geology 3. Secondary Education
UNIT
7The layers of the Earth
The biosphere
The biosphere is composed of all the living things that inhabit the layers of the Earth: the fish, the algae, etc., which live in the hydrosphere; the birds, the insects, etc., in the atmosphere; and the mammals, reptiles, spiders, plants, etc., which are on and in the crust of the geosphere.