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Lungs - your lungs

lungs; breathe; breath; breathing; oxygen; air; inhale; exhale;


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. We also need to breathe out carbon dioxide into the air. Carbon dioxide is made when our bodies use oxygen and other nutrients in our food to give us energy.

What are lungs? 

You have two lungs, which together form one of the largest organs in your body.

lungsThe lung on your 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. The lungs and the heart 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

lungs diagramHere is a diagram of the lungs.

If you could see them, they would look pink and rubbery on the outside. Inside they look a lot like sponges. Air comes down from your nose or mouth through 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 each tiny blood vessel. The blood carries the oxygen to the heart. The heart pumps all the oxygen-carrying blood to every cell in the body.

Breathing out

lungsAs each red blood cell empties its load of oxygen, it picks up carbon dioxide (say car-bon dye-ox-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.
lungs are cool!
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 materials burn in a house fire can be poisonous.

When lungs don't work well

Some people have asthma. Sometimes when they get a cold, are in contact with something they are allergic to, or exercise hard, the muscles in tiny tubes in their lungs get tighter making the tubes narrower 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 often they need medicines 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.

feeling unwellWhen lungs don't work well, that means 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
  • I get asthma and have a puffer to help me to breathe. I have another special medicine which I have to take every morning when there is a lot of pollen in the air. It stops the pollen making me wheezy when it gets into my lungs.

Some fun things about lungs

  • You breathe in about 11,000 litres of air every day.
  • When you are exercising you breathe in more air to send oxygen around to the muscles that you are moving.
  • On average, adults breathe between 12 and 20 times a minute when resting. Use a timer for check how many times you breathe when you are resting, and then when you have just been exercising.

Dr Kim says:

Dr Kim
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.

Don't smoke - it can damage your lungs

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We've provided this information to help you to understand important things about staying healthy and happy. However, if you feel sick or unhappy, it is important to tell your mum or dad, a teacher or another grown-up.


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