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Name: Josh
Status: Student
Grade:  9-12
Location: CA
Country: United States
Date: August 2006

Why would the mouth be a favorable location for bacteria?

Like any place on earh where the conditions are favorable...moisture, nutrients, temperature, competing organisms. The bacteria that populate the human mouth are rather different tha those of the dog for instance. If a person is helthy the system has evolved in a sort of symbiotic...commensalism....since our mouths are obviuosly not sterile, it is best that we have evolved with our bacteria to provide them with a home and they keep in check bacteria that good do us harm....if the balance is out of whack, we can end up with thrush.


Because the mouth is warm and wet which are ideal conditions (bacteria require water for growth and they multiply faster in warmer conditions). Also the mouth contains alot of nutrients for bacteria from the food which passes through the mouth. Lastly, the mouth is exposed to food and the environment which contain many bacteria.

Ron Baker, Ph.D.

To thrive, bacteria require a source of food, possibly oxygen depending upon the species, water, and warm temperatures. All these are constantly found in the mouth. However, there are also negative factors that control just how many bacteria can thrive at a given time. These include: there natural life span, chemicals found in saliva, swallowing which moves bacteria from the mouth to the stomach which is very acidic (pH about 2) which kills off many bacteria.

Vince Calder

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