BIOL 2051 Lecture Notes - Lecture 23: Lactobacillus Acidophilus, Propionibacterium Acnes, Tooth Enamel
Document Summary
Microbe populations change constantly: vary with type of tissue & condition. Intestinal flora varies with food eaten: can cause disease if reach abnormal location. There are billions of microbial cells living in & on the human body. Sites where bacteria are normally found: skin, oral cavity, gastrointestinal tract, respiratory tract, urogenital tract. Skin is difficult to colonize: dry, salty, acidic, protective oils. Microbes grow mostly in moist areas- underarms, genitals, etc. Associated with sebaceous (oil) glands & aprocrine (sweat) glands (ph 4-6) Factors that affect types of normal flora: weather, age, personal hygiene. Bacterial species commonly associated with the skin: most are gram-positive, staphylococcus. Propionibacterium acnes can cause acne: acinetobacter. Bacteria in the mouth prior to tooth formation are mainly aerotolerant anaerobes such as streptococcus & Acidic glycoproteins in saliva form a layer on teeth providing a firm attachment site for microbes, usually. Extensive growth of these microbes results in thick bacterial layers called dental plaque.
