Bio%20201%20S12%20Lect%2019%20%28True%29%20v3

Bldg rocio reminder ta oce hours

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: T, TH 11:20 AM - 12:20 PM Maria Roe M, W 12:00 - 1:00 PM Mohammad Nauman M 8:00 - 10:00 AM Muhaimin Rahman T 12:50 - 2:50 PM Rocio Ng M 3:00 - 4:00 PM, TH 9:00 - 10:00 AM Stephanie Tse F 11:45 AM - 1:45 PM Yuhang Chen F 2:30 - 4:30 PM parasiEsm is everywhere •  Sadava text, p. 1189: “Every species is eaten by at least one other species, and no species is enErely free of parasites and pathogens.” •  persistence of a parasite in a populaEon depends on infecEon of at least one new host individual (before current host dies) suscepEble hosts infected hosts recovered/ immune hosts each segment of the host populaEon has a birth rate and a death rate eyelash mites •  common in mammals, including humans •  usually no symptoms, undetected –  can someEmes cause rashes •  eats skin cells, oils, hormones •  frequency increases with age –  1/3 of children and young adults –  ½ of adults –  2/3 of elderly people role of evoluEon •  from contact to parasiEsm/disease –  evoluEonary pressure to reduce virulence unless host death is an important part of pathogen life history •  seems far beOer to be an asymptomaEc parasite than a lethal pathogen •  high mutaEon rates (someEmes due to error- prone replicaEon) –  arms race between pathogen and host immune system metazoan immune systems •  innate immune system: humoral (anEbodies), chemical defenses, inflammaEon –  evoluEonarily older and acEvates the adapEve immune system through anEgen presentaEon (next slide) •  adapEve immune system: immune cells have programmed recombinaEon of immunoglobulin (anEbody) genes –  new pathogen mutants are trying to invade –  immune system explores the structural space of immunoglobulin- anEgen binding •  posiEve feedback: when a pathogen is replicaEng, it induces an immune response – massive producEon of anEbodies that successfully bound to that anEgen DON'T WORRY ABOUT THIS SLIDE FOR THE EXAM hOp://en.wikipedia.org/wiki/ AnEgen_presentaEon From parasites to disease – Important scienEfic fields= infecEous disease epidemiology What is ”infecEous disease epidemiology”? •  Id...
View Full Document

Ask a homework question - tutors are online