From: Zardoz ®	10/11/2001 16:18:03
Subject: re: BODILY NOISES & FLUIDS FAQ	post id: 491236
Why do we humans burp and fart? The food we eat is digested in our mouth, stomach, small intestine, and large intestine. The digestive process involves decomposition (breakdown of larger molecules into smaller ones). Certain aspects of this decomposition produce gasses as byproducts. Most gasses are produced in the stomach or large intestine. Gasses tend to find their way out of any container in which they occur. Gasses produced in the stomach escape through the mouth when we allow them to (as when we burp). Gasses produced in the large intestine escape through the anus (when we fart). The gas produced as a byproduct of digestion is called flatus. Burping is also called belching. For some reason, the English word fart is considered vulgar and is often replaced with "passing gas" or "breaking wind." Dave Williams, Science Department Chair, Valencia Community College http://www.madsci.org/posts/archives/dec2000/977432499.Gb.r.html Why do we humans burp and fart ? Do bats fart? All mammals (in fact almost anything with a 'digestive tract') have bacteria living in their intestines. In humans it is often said that our bodies contain 10^14 living cells (a one followed by 14 zeros), only 10% of which actually belong to us. The rest are the bacteria that are living in the small intestine and colon, and that can be found on the skin, in the mouth and parts of the respiratory and genitourinary tracts. Within the gut, the bacteria ferment various sugars and other molecules present in the lumen of the intestine. Fermentation is one way in which organisms get energy from food. The basic fermentation of glucose produces ethanol and CO2 --> a gas. Fermentation of other sugars or molecules can produce hydrogen gas, methane and various sulphrous compounds (thus the bad smell). Your statement that diet may have something to do with it is entirely correct as the composition of bacteria in the gut depends on what is present as a food source, and what kinds of fermentation will take place. Lynn Bry, MD/PhD Student, Molecular Microbiology http://www.madsci.org/posts/archives/may96/831156548.Zo.r.html Bats Fart