BIOL 2051 Chapter : Chapter 23
Document Summary
Chapter 23- human microflora and nonspecific host defenses. Highly recommended that you read this chapter in the text. Human microflora: humans colonized by many microbes, normal flora. Commensal (mutualistic) organisms: microbe populations change constantly. Vary with type of tissue & conditions ph, moisture, other microbes present. Can cause disease if reach abnormal location. Metagenome-collective genome of all microbes in and on body. There are billions of microbial cells in & on the human body (majority are unknown & have never been grown in lab) Sites where bacteria are normally found: oral cavity, gastrointestinal tract. Dry, salty, acidic, protective oils, lysozyme: microbes grow mostly in moist areas-underarms, genitals, etc. Associated with sebaceous (oil) glands & apocrine (sweat) glands (ph 4-6) Factors that affect types of normal flora- weather, age, personal hygiene. Microbes commonly associated with the skin: most are gram + bacteria: Human microflora: eye: most inhibited by lysozyme & continual rinsing of conjunctiva (eye surface)
