Vinyl chloride, chloromethane and the banned pesticide DDT are examples of chlorinated hydrocarbons. Chlorinated hydrocarbons are organic molecules wherein chlorine has been substituted for some of...
Resident flora of certain areas plays a definite role in maintaining health and. normal function. Members of the resident flora in the intestinal tract synthesize. vitamin K and aid in the absorption of nutrients. On mucous membranes and. skin, the resident flora may prevent colonization by pathogens and possible. disease through âbacterial interference.â The mechanism of bacterial interference. is not clear.
THE COMPOSITION OF THE NORMAL FLORA It has been calculated that the normal human is host to about 1012 bacteria on the skin, 1010 in the mouth, and 1014 in the gastrointestinal tract. Normal Flora of the Skin. An adult is covered with approximately 2 square meters of skin.