How Breathing Works
Know that we breathe air into our lungs through the nose and mouth, that our lungs take in oxygen from the air which our body needs to stay alive, and that we breathe out carbon dioxide as waste
What a learner can do afterwards
- Trace the path of air: nose/mouth → windpipe → lungs
- State that lungs take oxygen from the air, which the body needs
- State that we breathe out extra carbon dioxide made by the body
1 · Read
You breathe all the time to stay alive, even when you run and play. Air comes in through your nose or mouth. It moves down a tube called your windpipe to your lungs.
Ben runs fast at recess. Air goes in through his nose, down his windpipe, and into his lungs. His lungs pull oxygen out of the air, and his body needs that oxygen to keep going. Running uses oxygen faster, so Ben needs more of it. That is why he breathes faster when he runs.
Your lungs take in oxygen and remove extra carbon dioxide. Your body makes this waste gas as it uses food for energy. You breathe it out.
Air comes in, lungs take oxygen, and you breathe out carbon dioxide.
The rewritten readings were written for this dataset.
More to read
What a breath brings in and takes out
Oxygen is a gas in the air that keeps you alive. Take a breath, and air enters your nose or mouth. It travels through your windpipe to your lungs.
You have two soft, spongy lungs in your chest. Oxygen passes from the air in them into your blood. The blood carries it around your body.
Your body makes another gas, carbon dioxide, as waste. Extra carbon dioxide passes into your lungs and leaves with the air you breathe out.
Each breath brings in oxygen and carries away carbon dioxide. Your nose helps prepare the incoming air by warming it and trapping dust before it gets to your lungs.
The route air follows
Your breathing parts work together in two groups. Air first passes through your nose or mouth, then your throat. The spaces inside your nose belong to this first group too. Your nose warms incoming air.
The other group includes your windpipe and lungs. Air travels down the windpipe towards your chest. It reaches smaller tubes that divide again and again inside your lungs, like tree branches.
In the lungs, oxygen enters your blood from the air. Carbon dioxide, a waste gas, moves out of your blood and into the air you will breathe out.
These parts keep working together with every breath, through the day and night.
Your chest moves as you breathe
Breathing happens on its own, even while you sleep. Your chest grows bigger as you take air in. Air enters at your nose or mouth and passes through the windpipe to your lungs.
Your lungs supply oxygen, a gas your body needs to stay alive and release energy from food. Your body also produces carbon dioxide, a waste gas.
As you let a breath out, your chest becomes smaller. Air carries the waste gas away.
Your ribs form a cage around your lungs. They protect them while you keep breathing.
Explore more
2 · Watch
En anglaisTake it off screen
Where it sits
Learn first
Nothing; this is a starting point.
This opens up
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.