Biology M200 1st Edition Lecture 11 Outline of Last Lecture I. Controlling microbial growth in the bodyOutline of Current Lecture I. Infection: RelationshipsCurrent LectureSymbiosis- Close association between two or more organisms.Commensalism- Your body shelters trillions of microorganisms- 1cm^2 of skin contains 3 million bacteria, yet most of your body is sterile. - Normal Microbiota: large populations of bacteria that normally live in/on our bodies.- Skin, upper respiratory system, intestines, reproductive system.Commensalism to Mutualism- Passive protection is known as microbial antagonism or microbial competition- Normal microbiota use nutrients, take up space, and release toxic waste products.Acquisition- Normal microbiota colonize humans during birth (womb is normally sterile)- Much of the normal microbiota are established during the first months of life.Mutualism- Ruminants: animals with a rumen, and organ containing bacteria- Bacteria digest cellulose- Cow then digests products made by bacteria.Parasitism- Pathogens: infect the body and kill our cellsThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- A way to obtain nutrients (Pathogens)Pathogenesis Terms- Contamination- presence of a microbe in or on the body- Infection- persistence of a microbe in or on the host body (may or may not cause disease)- Pathogen- a microorganism or agent that is able to cause disease.- Disease- any defect in body function caused by infection.- Pathogenicity or virulence- the ability to cause disease.- Virulence factors- microbial products that contribute to pathogenicity.Infection- Portal of entry: routes by which microbes gain entry to the bodyVirulence Factors- Properties of the bacterium that allow them to be pathogens- Enhance: invasiveness (the ability to enter and survive in the body) and/or Toxicity (the ability to damage cells and obtain nutrients.- Motility: Tissue tropism- some bacteria infect particular parts of the body. Motility can aid in tropism (migration) to target tissues.o Extracellular enzymes: dissolve structures in the body, enable bacteria to invade deeper tissues.- Adhesins: bacterial proteins that bind to sugar patterns on human cells.Evasion- Extracellular enzymes- Coagulase: causes clots to form, enables bacteria to hide from immune response.- Kinase: digests clots, allows subsequent