MCB 2000 Chapter Notes - Chapter 13: Opportunistic Infection, Gram-Negative Bacteria, Neuron
Document Summary
Three types of microorganisms are associated with human body: normal microbiota microorganisms colonizing the human body without harming it, transient microbes rapidly lost, pathogenic microbes invade and damage the cells and tissue. Acquiring resident biota: the uterus is germ-free, first exposure to microbes occurs during the passage through the birth canal, feeding, contact with the environment and family members. The progress of infection: infection starts with an invasion of a pathogen, how successful this invasion will be, depends on: Pathogenicity the ability of a microbe to cause disease in another organism. Virulence the degree of pathogenicity; relative ability of a microbe to cause a disease: virulence factors (enzymes, toxins, capsule ) Establishing the infection: the microbes enter the body through -portal of entry. Portals of entry: mucous membrane (lines the body cavities that are open to the environment, skin (openings or cuts)
