Women's and Children's Health Network
Your lungs
Kids' Health Topic
Have you ever looked at the sky and thought about whether there are other people living out
there? Well, according to those scientists who study these things, there are no other people,
animals or plants like us out there in our solar system, because no other planet has air like
ours.
Why do we need air? Because we could not survive without the oxygen in the air that we
breathe. We could not take in the oxygen if we didn't have lungs.
What are lungs?
You have two lungs, which together form one of the largest organs in your body.
The lung on the left is a bit smaller than the lung on the right because it has to make room for
your heart to fit in your chest too. They need to be close together because they work together.
Your rib cage goes around your lungs and heart to protect them from damage. Your ribs also
move when you breathe in and out.
Below your lungs is the diaphragm (say dye-a-fram). This is a big muscle that works with your
lungs to get air in (inhale) and out (exhale).
You can feel how they work together.
1. Put one hand on your chest and the other on the upper part of your tummy.
2. Now breathe in deeply. You will feel your chest and your tummy get bigger as the air
goes into your lungs.
3. When the diaphragm contracts (gets tighter) it pushes some of the organs in your
tummy down so that there is more space in your chest.
What lungs look like
If you could see them, they would look pink and rubbery on the outside. Inside they look a lot
like sponges. Air comes down the trachea (say trak-ee-a), or windpipe, into two large tubes
called the bronchi (say bron-key). One bronchus (say bron-kuss) goes into the left lung and
the other into the right.
Each bronchus is rather like the trunk of a tree because it has what look like branches and
twigs growing from it. The smallest 'twigs' are called bronchioles (say bron-key-oles). They
are so tiny that they are like hairs.
At the end of these bronchioles there are little bunches of alveoli (say al-vee-o-lie). These are
sacs, or little bags, full of air. There are about 600 million of them in your lungs, so you can
imagine how very tiny they must be and what a powerful microscope you would need to look
at them!
Each tiny alveolus (that's the name for one of them) is covered in even tinier blood vessels
called capillaries (say ca-pill-a-riz).
Each part of your lungs has an important role to play.
Breathing in
When you inhale, or breathe in, the air goes in through your nose or mouth. Little hairs called
cilia (say silly-a) inside your nostrils catch tiny particles of dust. If they don't catch all of them,
there are more cilia and mucus inside your trachea, which trap the dust and stop it from
getting into your lungs.
Your diaphragm flattens out (contracts), your ribcage lifts and the air goes through all the little
branches in your lungs to fill up the air sacs, or alveoli.
Oxygen goes through the walls of the alveoli and into the capillaries where the oxygen enters
the red blood cells in all the tiny blood vessels, which then carry the blood towards the heart.
The heart pumps all the oxygen-carrying blood to every cell in the body.
Breathing out
As each red blood cell empties its load of oxygen, it picks up carbon dioxide (say car-bon dyeox-eyed) from the cells and heads back to the lungs.
The carbon dioxide is carried by the red blood cells in the lungs' capillaries to the alveoli,
where it is emptied into the air that leaves the body when you breathe out.
For you to exhale, or breathe out, the diaphragm relaxes, muscles between the ribs relax and
air is pushed out of the lungs.
This air then goes up through all the bronchioles, up the bronchi, up the trachea and out
through the nose or mouth.
Look after your lungs
1. Don't smoke and keep away from others who smoke. Lungs do not like cigarette
smoke - it can damage them, and cause disease and even death.
2. Stay out of the workshop if someone is using chemicals, as some can damage your
lungs. Remind mum she should wear a mask and have windows open if she is using
some chemicals, like when she is cleaning the oven or using drain cleaner.
3. Get plenty of exercise. It makes the muscles around your lungs work harder and
makes them stronger.
4. If there is a fire in your home or school, stand well back from the fire as breathing
smoke can be bad for your lungs. Have you noticed how firemen wear special masks
when they are fighting fires? The heat from smoke can burn the tiny bronchioles in
your lungs and some chemicals that are made when plastics and other material burn
in a house fire can be poisonous.
When lungs don't work well
Some people have asthma. Sometimes when they get a cold or exercise hard, the tiny tubes
in their lungs get tighter and there is a lot more mucus. This makes it hard to get air into the
alveoli. They can become very short of breath and sometimes they need medication to help
their lungs work well. Our topics on Asthma can tell you more about it.
Illnesses like bronchitis (say bron-kite-us) and pneumonia (say new-mow-nee-a) also make it
hard for air to get into the alveoli.
_____________________________________________________________________
-2http://www.kids.cyh.com
Last updated: January 2011
When lungs don't work well, that means that there is not enough oxygen getting round to all
the cells of the body, and the body systems don't work as well as usual.
 You feel short of breath.
 It feels like you don't have any energy and can't do things.
 It feels like you just want to lie down and rest or sleep.
Kids say
 "When I was four I went to hospital. I had asthma and I had a special thing on my finger. I
had to breathe in a mask. My dad was reading to me."
 "I've had pneumonia before. I was in hospital for 5 days. I had to have an oxygen mask
because my lungs would not work properly. They were all blocked up."
 "I had food poisoning. I couldn't breathe and I had a mask and I couldn't eat. I was in
hospital for four weeks. It was really boring." Lizzie
 "My house was on fire. My brother got me out but I was really coughing and I couldn't
breathe. I had to have a mask with oxygen and my chest hurt for a few days but I'm alright
now."
 "My grandpop had cancer in his lungs and he died. He used to smoke a lot. I miss him."
Carly
Dr Kim says:
Every person breathes all the time. Breathing is so important that you don't have to spend all
your time thinking "breathe in, now breathe out" - your body does that automatically. Take
care to exercise your lungs and keep them away from harmful things, especially cigarette
smoke.
_____________________________________________________________________
-3http://www.kids.cyh.com
Last updated: January 2011