Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
36 Cards in this Set
- Front
- Back
|
animal hosts
|
favorable environments for grwoth of microorganisms where most dont harm
|
|
|
normal microbial flora
|
mutualists and commensals, live on hosts(humans) w/o causing problems and provide host with benefits(vits)
|
|
|
parasites
pathogens |
take from host w/o giving back
microbial parasites |
|
|
pathogenicity and pathogens
opportunistic pathogen |
infection to the host by pathogens can lead to disease. pathogenicity is ability to cause disease.
cause disease only in absence of normal host resistance |
|
|
mucous membrane
|
coated with protective layer of viscous soluable glycoproteins (mucus) and are the common site of microbial attachment/infection.
|
|
|
skin as host
|
harsh enviro, most dont grow
skin flora:transient and resident populations resident(gram +) live near apocrine(moist) or sebaceous(nutrient) glands |
|
|
oral cavity
|
variety of nutrients,lysosyme and lactoperoxidase inhibit cell growth. glycoproteins from saliva provide stickiness for attachment.
|
|
|
biofilm of oral cavity
|
aka dental plaque, is colonized by other bacteria.
lower layers of it become anoxic allowing growth of anaerobes like actinomyces. |
|
|
stages of biofilm formation
|
attachment:cells to solid surface
colonization:intercellular communication,polysac form development:extensive growth |
|
|
plaque growth
|
leads to pdtion of organic acids and tooth damage.
S.mutans doesn't need glycoproteins for adhesion bc makes its own dextran |
|
|
abdominal physiological processes and amt of bacteria
|
stomach:secretion of HCl,digestion of macro's (few,pH 2)
SI:abs monosac,aa,FA,H2O (10e6-10e7,pH 4-5) LI:abs of bile acids,vit B12 (10e10-10e11,pH 7) |
|
|
biochemical/metabolic contributions of intestinal microo
|
vit synthesis:B12,K,thiamine
gas pdtion:CO2,CH4,H2 odor pdtion:H2S,NH3,acid organic acid pdtion:acetic,propionic,butyric acids glycosidase rxns:beta-glucuronidase...other betas steroid metab:esterification,dehydroxylation,oxidation,inversion |
|
|
respiratory tract
|
upper:(naso,oral,throat)many bacteria
lower:(trachea,lungs)no resident bacteria healthy carriers harbor pathogenic, resident flora limit pathogen by competing for resources. |
|
|
bladder and reproductive organs
|
healthy bladder is sterile but urethra colonized by facultative anaerobes.
vagina is host to complex community (age dependent). normal flora regulate pathogens |
|
|
microbes...most dont "want" to kill
|
exposure:to pathogen
adherence:to skin, mucosa invasion:thru epithelium colonize/growth:toxicity(local) and invasive(systemic) tissue damage/disease |
|
|
parasites relative ability to cause disease (virulence)
|
highly:streptococcus pneumonia
moderately:salmonella typimurium virulence determined by toxicity and invasiveness attenuated:inable to cause disease |
|
|
virulence factors aid in adherence to specific host epithelial tissues ie...
|
pili
slime layers and capsules may protect cells from host immune system |
|
|
major adherence factors to facilitate attachment to host
|
slime/capsule:e.coli,mutans
adhere protein:pyogenes,gonorrhoeae lipoteichoic acid:pyogenes fimbriae(pili):neisseria gonorrhoeae,salmonella,e.coli |
|
|
enzymes; other virulence factors
|
hyaluronidase,collagenase:breakdown intracellular streptokinase:dissolves clots
nutrient whores:protease,nuclease,lipase,siderophores,TR |
|
|
bacterial toxicity from 2 types of toxins
|
endo:intrinsic to bacteria mem
exo:potent,released by cell. 1.cytolitic 2.A-B toxins:botulism 3.super-Ag toxins |
|
|
cytolytic toxins
(aka hemolysins) |
kill host cell, not all are specific
hemolysins:dissolve mem lipids to lyse or sterols |
|
|
A-B toxins
|
two subunits
one binds the cell receptors other affects the cell |
|
|
botulism toxin
|
most potent biological, results in flaccid paralysis
|
|
|
tetanus toxin
|
opp of botulism, results in rigid paralysis
|
|
|
enterotoxins
|
exotoxins that specifically target the SI and have 3 different types
|
|
|
endotoxins
|
part of the outer membrane of gram -(lipid A of LPA) and are less toxic than exotoxins
|
|
|
salmonella
|
variety of virulence traits:
entero,sidero,endo,O-Ag,cyto,capsule |
|
|
carriers
|
hosts of pathogens that dont have the disease
|
|
|
influences of infection
|
age,stress,diet,health,genes
compromised hosts are at additional danger for infections caused by opportunistic pathogens(noscimial infections) |
|
|
anatomical defenses
|
skin
rapid pH change flushing urinary tract nasopharynx mucus in trachea blood proteins mucus/phagocytes in lungs stomach acidity |
|
|
parasites relative ability to cause disease (virulence)
|
highly:streptococcus pneumonia
moderately:salmonella typimurium virulence determined by toxicity and invasiveness attenuated:inable to cause disease |
|
|
virulence factors aid in adherence to specific host epithelial tissues ie...
|
pili
slime layers and capsules may protect cells from host immune system |
|
|
major adherence factors to facilitate attachment to host
|
slime/capsule:e.coli,mutans
adhere protein:pyogenes,gonorrhoeae lipoteichoic acid:pyogenes fimbriae(pili):neisseria gonorrhoeae,salmonella,e.coli |
|
|
enzymes; other virulence factors
|
hyaluronidase,collagenase:breakdown intracellular streptokinase:dissolves clots
nutrient whores:protease,nuclease,lipase,siderophores,TR |
|
|
bacterial toxicity from 2 types of toxins
|
endo:intrinsic to bacteria mem
exo:potent,released by cell. 1.cytolitic 2.A-B toxins:botulism 3.super-Ag toxins |
|
|
specificity in infectious disease
[disease,tissue infected,organism] |
AIDS,T-helper,HIV
botulism,motor end plate cholera,SI dental,oral epi,mutans diptheria,throat epi gonorrhea,urogenital malaria,blood(erythro) pyclonephritis,kidney,proteus spontaneous abortion,placenta tetanus,inhibitory interneuron |
