Page 151 - DK Children's Encyclopedia

Lungs SEE ALSO

▸ ▸ Brain p.45
▸ ▸ Gases p.117
We breathe air in and out of our lungs. The lungs take ▸ ▸ Heart p.128
oxygen from the air and transfer it to the blood. Every part ▸ ▸ Human body
of the body needs oxygen, so the lungs collect it and the p.130

blood carries it around the body. ▸ ▸ Skeleton p.228
▸ ▸ Sound p.235

Nose
Lungs Air enters and leaves
our bodies through
The lungs are two spongy bags our nose and mouth.
filled with tubes and air sacs. The Oxygen is taken
air sacs are where gases change into the blood and
carbon dioxide is
places. Oxygen is breathed in and sent out of the
carbon dioxide is breathed out. blood in the air sacs.
Trachea
This tube carries air
into our lungs. It is
also known as the
windpipe.
Bronchi
These two air tubes
connect the trachea
to the lungs.

Bronchioles
The air goes into
these tiny tubes.
Each one ends in air
sacs called alveoli.

Alveoli, or air sacs
Diaphragm
This muscle changes
the shape of the
lungs so we can Voice box
breathe in and out.
The voice box is in the throat.
It stops food from getting into
the lungs and makes us cough
Breathing if any food gets in. The voice
Muscles work Air enters the Air leaves the box also lets us speak and sing.
together to let lungs as we lungs as we
breathe out.
breathe in.
us breathe in and
out. We have a The rib muscles The rib muscles
diaphragm muscle pull up to make relax so the
below the lungs the ribcage ribcage gets
bigger.
smaller.
and more muscles
around the ribcage. The diaphragm The diaphragm
They change the pulls down to relaxes and
size and shape of pull air into the the lungs get
smaller, pushing
lungs. The lungs
the lungs. get bigger. air out.

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