Pathogenic Factors Flashcards
Resident microbiota _ colonize the host (after birth)
permanently
Transient microbiota _ colonize the host (dependent on the environment)
temporarily
When would normal flora cause us harm?
If it moves from where it is supposed to be to another part of the body
T/F; normal flora will look the same on an abled bodied person and a disabled person
False
What is microbial antagonism?
Normal flora preventing the growth of pathogenic microbes
T/F: normal flora competes for nutrients with a pathogen
True
T/F: when normal flora is exposed to a pathogen it will be unable to fight it off
False; they produce substances that are harmful to the pathogen
_ produce bacteriocins
E. coli
_ are proteins that inhibit the growth of closely related species of bacteria such as salmonella and shigella
bacteriocins
When would dormant spores wake up?
When normal flora is destroyed because it no longer needs to compete for nutrients
_ is a pathogen that causes a range of GI symptoms, from mild diarrhea to severe, or even fatal colitis
C. diff
Presence of normal flora in the large intestine inhibits the growth of _
C. diff
What are the 5 steps of a pathogen causing disease?
- contact/exposure
- adherence
- evasion of host defenses and penetration
- damage of host cell
- transmission
Adherence is accomplished by cell surface molecules located on the pathogen called “” binding specifically to surface “” located on the cells of the host tissues
adhesins ; receptor
What are 3 different ways a pathogen can adhere to a host?
- bacterial structures (fimbriae, pili, flagella)
- adherence proteins (M protein, opa protein)
- glycocalyx (capsule, slime layer)
Adhesins are present on the _ and _ of many pathogenic bacteria
fimbriae and flagella
T/F: the more types of adhesion proteins an organism has the more systems they can infect
True
If the glycocalyx is well organized and firmly attached to cell wall, it is referred to as a _
capsule
If the glycocalyx is unorganized and only loosely attached to the cell wall, it is referred to as _
slime layer
The slime layer facilitates the formation of _
biofilms
_; colony of bacteria that adheres to surfaces (living and nonliving), embedded in an extracellular slime layer
biofilms
T/F: biofilms are able to clog drains and corrode industrial pipes
True
_ impairs phagocytosis, preventing phagocytic cell from adhering to the microbe, thereby increasing the virulence of the pathogen
capsule
T/F: those without a capsule cause infection more quickly because it does not need to break through to infect the host
False; those without a capsule rarely cause infection because they are detected quickly by the immune system
M proteins _ virulence by helping bacteria resist _ by WBC (e.g. streptococcus pyogenes)
increase ; phagocytosis
_ present in the cell wall of Mycobacterium TB increases virulence by resisting digestion by phagocytosis
Mycolic acid
_ clot protects the bacteria from phagocytosis, and isolates the microbe from other defenses of the host
fibrin
Coagulase is produced by some _ spp.
staphylococci