Breathe in. Breathe out. Breathe in. Breathe out. Your lungs repeat this routine about 15 to 25 times each minute, without you even having to think about it. Breathing is an autonomic response; you couldn’t stop it, even if you tried.

When you breathe in, your lungs gather the oxygen from the incoming air and exchange it for carbon dioxide, a waste product that your body then expels as the lungs breathe out. The lungs have an important job. They are part of the respiratory system that circulates about 10,000 quarts of air through your system each day to deliver oxygen to every cell in your body.

You probably know that they lungs are located in your chest cavity and are surrounded and protected by your ribs. You might not know that the left lung is a little bit smaller than the right lung; this is in order to make room for the heart. Because of this size difference, the right lung has three lobes – the upper, middle and lower; the left lung only two – the upper and lower lobe.

The lungs themselves are made up of sponge-like elastic tissue. As they expand with air, the tissue stretches and the air pockets in the “sponge” absorb oxygen. When we exhale, the lungs constrict, like a sponge that’s squeezed tight, and old air (carbon dioxide) is released.

As you breathe in air, it travels through your nose or mouth into the trachea. From there it travels until it reaches the bronchi. The bronchi splits into two tubes and passes the air into each lung where it travels through tiny tubes called bronchioles. The bronchioles get smaller and smaller until they reach the alveoli – tiny air pockets where the gas exchange occurs. There are about 600 million alveoli in your lungs, so you can imagine how tiny they are. Oxygen diffuses through the alveoli into the pulmonary capillary and is transported throughout the body. At the same time, carbon dioxide makes the opposite trip – from the pulmonary capillary to the alveoli and so on until you breathe out releasing it into the air.

Because breathing – and the work that the lungs do – is so important, it’s vital that you keep this important organ healthy. Your lungs are directly affected by the air you breathe. If you breathe in contaminants or pollution, they enter your lungs. How to protect them? Don’t smoke. Avoid secondhand smoke. Pay attention to pollutants in the environment – both indoors and outdoors.

Engage in healthy lifestyle habits to prevent colds or respiratory infections. Wash your hands often and keep them away from your mouth and eyes. If a friend or family member is ill, avoid direct contact with them.

Good oral hygiene is important for preventing infection. Brush your teeth at least twice a day – morning and night.

Get vaccinated each year for influenza. Ask your health care provider if the pneumonia vaccine is recommended for you. If you do get sick, do not spread your germs to others. Stay home – from work and other activities.

Get plenty of exercise. This makes the muscles around your lungs work harder, and in the long run makes them stronger.

There are certain diseases and conditions that make the lungs work harder, or make them less able to do their job. Certain symptoms may serve as warning signs of lung problems or lung disease. If you have a chronic cough, shortness of breath that doesn’t go away, extreme fatigue or exhaustion that seems to be related to your breathing capacity, chronic mucus, wheezing, cough up blood or experience chronic chest pain that gets worse when you breathe or cough, contact your health care provider so he or she can complete a more thorough evaluation of your condition.

Your lungs: They work hard every day doing a simple, yet complex, task of supplying every cell in your body with oxygen, while removing carbon dioxide waste. Breathe in. Breathe out, and when you do, remember the lungs and the important work they do.