Your lungs are part of what is called the respiratory system, a group of organs and tissues that work together to help you breathe. This brochure explains the parts of the respiratory system and how they function.
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How We Breathe
Breathing in and out may be something you don't think about very much. This may change when you have a cold, an asthma attack, or an illness that makes it hard to breathe. To better understand things like chronic obstructive pulmonary disease (COPD) and asthma, let's see how breathing happens in normal, healthy lungs.
Your lungs are part of what is called the respiratory system, a group of organs and tissues that work together to help you breathe. The respiratory system's main job is to move fresh air with oxygen into your body while removing air with carbon dioxide from your body.
The respiratory system also does other things that are important for breathing, such as:
Breathing by the Numbers
Your lungs help you breathe 12 to 15 times a minute when you are resting—that's over 6 million breaths in 1 year alone!
Think of the respiratory system as a pipe in which all parts are connected and each area affects another area.
Here are the parts of the respiratory system:
The inside story of the lungs
When you take in a breath, the air is filled with oxygen. The air goes down your windpipe into the bronchial tubes. These tubes branch out further into thousands of smaller, thinner tubes called bronchioles when they reach the lungs. At the end of the bronchioles are groups of tiny, round air sacs called alveoli.
When the air you breathe in reaches the air sacs, the oxygen passes into tiny blood vessels called capillaries, which run through the alveoli's walls. At the same time, carbon dioxide, the waste that comes from the cells after they use the oxygen, moves out of the capillaries into the alveoli. This is called a gas exchange. Life-sustaining oxygen now fills the blood vessels and is delivered throughout your body. The air that contains the carbon dioxide then moves up and out of your lungs.
The bronchial tubes and air sacs are very stretchy. When you breathe in, each air sac fills up with air like a balloon. When you breathe out, the air sacs deflate.
Lung capacity decreases as you get older. You can help keep lungs healthy by not smoking, eating a healthy diet, exercising, and managing your stress.