name some normal flora locations
- anything in a mucous membrane
- outer ear
- small and large intestines
name some locations where it is sterile (no normal flora)
- anything inside, in body cavity
what are some predisposing factors?
- short urethra in female
- inherited traits
- climate and weather
- lifestyle (smoking, etc)
- cancer patient
- physical and mental stress
What is the "lethal dose"?
how much toxin it takes to kill 50% of population (LD50)
What is the "infective dose"?
minimum number of microbes required for infection to proceed (ID50)
What is needed for an infection to occur?
- infectious dose
- portal of entry
- way of invasion, passing through
- must invade host defense barrier (surrounds sterile compartment)
- portal of exit (to go and spread to other hosts)
what is the source of an exotoxin?
mostly gram +
exotoxins are products of what?
by-products of growing cell
what are exotoxins made of?
do exotoxins cause fever?
can exotoxins be neutralized by antitoxin?
what is the LD50 of an exotoxin?
what is the source of an endotoxin?
mostly gram -
endotoxins - metabolic product
present in LPS of outer membrane
what are endotoxins made of?
do endotoxins cause fever?
can endotoxins be neutralized by antitoxin?
what is the LD50 of an endotoxin?
what does LD50 mean?
lethal dose, amount it takes to kill 50% of population (test area)
what are some mechanisms of adhesion for bacteria?
- fimbrae, flagella
- cilia, suckers, hooks, barbs
- hydrophilic (nonspecific)
- van der Waals forces
- adhesion proteins (specific)
- host cell receptor sites