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Lesson 10 of 17

The path of air

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5 min

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You breathe in. Where does the air go?

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The idea

Air carries dust.
Step 1 of 7
  1. Air carries dust.
  2. It enters through two nostrils, the two holes in the nose.
  3. In the nasal passages, hairs and sticky mucus trap dust and dirt.
  4. The windpipe carries air down.
  5. It splits in two, one branch for each lung.
  6. The finest branches end in tiny sacs full of air: the alveoli.
  7. The rib cage is a bony cage round the lungs.

Air goes in through the nostrils and nasal passages. It passes down the windpipe and its branches to the alveoli.

Hairs and mucus trap dust. So the nose cleans the air first. Breathing through the mouth does not clean the air this way.

Watch out!

Air goes down the windpipe, not the food pipe. Food takes the other path.

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