Lecture 8- Innate Immunity Flashcards
what does the immune system do?
fights off foreign material that threatens the body and protects against disease
what are the two different types of immunity?
innate
adaptive
what is adaptive immunity?
highly specific
what is innate immunity?
non- specific
what does the innate immune system specifically do?
protects humans from most infectious diseases
when does immunity start?
at birth and is always present
what is natural host resistance?
host resistance has no memory but our susceptibility to pathogens varies from one species to another
what is an example of how susceptibility to pathogens varies from one species to another?
HIV can infect human cells but not mice
anthrax causes fatal blood infection in cattle but just a minor skin infection in humans
can the immune system be specific?
YES can be specific for a particular tissue
can pathogens be specific?
yes! they prefer a specific body site to initiate infection (some have specific receptors and bind to specific cell types)
how can pathogens spread?
aerosols (sneezing)
bodily fluids (blood)
what is Clostridium tetani?
anaerobic and thus prefer to live in our anaerobic bodies, can be ingested or can enter into deep wounds. this is why we get tetanus shot to prevent microbes like this
how does the innate immune system protect us? what barriers/ defenses does it have? (5)
physical barriers
chemical defenses
cellular defenses
molecular defenses
physiological processes
what are two main barriers to infection?
skin
mucous membranes
how does the skin act as a physical barrier?
prevents invasion by microbes because its slightly acidic (pH 5) which microbes dont like
high NaCl (because salty microbes dont like this)