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Lesson 6 of 13

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6 min

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Earth acts like a giant magnet. This helps keep us safe from space.

The atmosphere is the air.
Step 1 of 4
  1. The atmosphere is the air.
  2. The hydrosphere is all the water.
  3. The geosphere is rocks, soil and minerals.
  4. The biosphere is all living things and where they live. The four work together.

The rule

A particle is a very tiny piece of matter. A cell is the basic building unit of life.

Cosmic rays and the solar wind are fast particles from space. They can harm the air and living cells. A magnetic field is the space where a magnet's force acts.

Earth has the right distance, the right size and a magnetic field. The magnetic field pushes many harmful particles away. Lose any one, and life is at risk.

Living things depend on each other and on the other three spheres. A small change, like cutting a forest, affects the other parts too.

Switch each thing on or off. Can life thrive, that is, live and grow well?

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