MAIN Health The Human Body The Lungs

If you've ever tried to hold your breath for any length of time, you know how important the lungs are in the overall functioning of the human body.

The main job of the lungs is to take oxygen from the atmosphere and put it in the bloodstream, while simultaneously taking carbon dioxide out of the blood stream and ejecting it in to the atmosphere.

How the lungs work

The lungs perform this vital role by contracting and expanding, a job performed by the diaphragm muscle.

The diaphragm, in turn, receives signals from the brain telling it when to speed up (while you are running or exercising) or when to slow down (while you are at rest or sleeping).

When the diaphragm contracts, the lungs are pulled downwards, and their capacity is increased, which pulls air in. The diaphragm then relaxes, and whatever oxygen was not absorbed by the body, along with the carbon dioxide being ejected by the body, is allowed to leave the lungs.

In addition to providing the body with oxygen-rich blood, lungs are partially responsible for acting as a protective cushion for the heart which they almost completely surround. Meanwhile, surrounding the lungs, lymph nodes also help the body filter out germs and impurities.

Keeping lungs healthy

Keeping your lungs healthy is a relatively easy thing to do.

If you don't smoke, don't start! And if you do smoke there are various quit smoking programs that may help you kick the habit.

Another sure way to keep lungs healthy and happy is to avoid environmental pollution wherever possible. Obvious things like staying away from heavily polluted city centers are important, but air pollution can often be found in the home, as well.

Dirty appliances such as air conditioners can contribute to indoor air pollution, and overly moist environments are havens for household bacteria. Especially during the winter, arm yourself against pneumonia, the common cold or flu by simply opening a window — to provide fresh supplies of oxygen to help your lungs fight off cold weather bugs.

More about the human lung around the Web:

Your Lungs - Illustrations and information detailing how humans breath with related Flash presentation, with guides to keeping lungs healthy and warning signs of disease, from the American Lung Association.

Breathing in the Air - The Lungs - Photos in cross-section and information on how air enters and leaves the body, charts explaining how air's chemical composition changes as it is inhaled and exhaled, with related chapters on the breathings systems of plants and animals.

Lungs, Lung Information, Breathing Facts, News, Photos - Explore National Geographic for information on lung anatomy, how they work, related facts on asthma and related diseases, feature articles and photos.

also see in Health -> COPD Symptoms & Treatment

Lung Cancer Causes, Symptoms & Treatment

Asbestos Dangers - A Homeowner's Field Guide