I’m taking an anatomy and physiology class and it really makes me see just how incredible life is. It’s so complex and we don’t even realize it. We’re like reasoning robots in a way. I think we also don’t realize how important all those things we think are so gross really are. So my question is: explain the main purpose of mucous?

The skin and mucous membranes form the body's first line of defense against disease. Most microscopic pathogens, or microbes, cannot pass through unbroken skin, although they can easily enter through cuts and other wounds. Mucous membranes protect internal organs that are connected with the outside of the body. These membranes, which line the respiratory, digestive, urinary, and reproductive tracts, secrete a sticky fluid called mucus, which traps microbes. The mucus may then be expelled from the body, perhaps in a cough or sneeze or in feces. If the mucus is swallowed, digestive juices kill the microbes.



"Human Disease," Microsoft® Encarta® Encyclopedia 2000. © 1993-1999 Microsoft Corporation. All rights reserved.