Boogers are the dried-up leftovers of this fluid your body produces called mucus. Mucus is a mixture of polysacchariades (a big word for a long chain of sugars linked together) and water. Let me ask you this...what do you think boogers do for us? I'll give you a clue. Imagine you are walking down a dusty road to your friend's house. The wind is blowing and all of this dirt and dust is getting blown in to your face. Now you take a deep breath, but for some reason the dust and dirt does not seem to hurt your lungs. What do you think is happening? Remember, as you breathe in the air passes by all that mucus.

Let me know what you find out!

Scientists call "boogers" mucus.We make mucus in many areas of the body where delicate tissue must be protected from chemicals, germs, or abrasion. Cells secrete mucus, which is a mix of water, proteins, and other materials. It is in your stomach to protect against acid, in your food tube (esophagus) and gut to allow food and foreign material to slide along without scraping the tissue on the side. It is in the reproductive tract of both sexes. The mucus in your nose comes from the nose itself and the lining of the air passages. Normally, the nose and sinuses produce between a pint and a quart of mucus and secretions per day. The water can evaporate, so dried mucus may be in the nose. The rest is swallowed.

There is mucus in the lungs. It protects lungs against germs and pollution. Little hair-like things called "cilia" push the old mucus up the windpipe to get rid of the stuff trapped in the mucus. We usually swallow this without bringing it up to our mouths, but coughing can bring it all the way up.

Smoking paralyzes the cilia, so they can't move up the old mucus. It and the junk trapped in it stays in the lungs a lot longer.

See a picture of the sinuses at:
http://home.earthlink.net/~jodette/sinusitis.html