BASIC - LAB 3 Flashcards
what is the ability of an organism to cause disease
pathogenicity
why are some bacteria highly virulent
due to the presence of virulence factors
______ refers to the degree of pathogenicity within a group or species of microogranisms
virulence
presence of virulence factors ______ host deferenses, assist bacterial survival, and damage tissues
decreases
strict pathogens are ___ associated with pathogenicity such as ___ and ____
always
m. tb, n. gonorrhoeae
____ take advantage of the environment and a compromised host to cause infection
opportunistic pathogens
what bacteria typically colonize in host as normal flora and are often beneficial to host
commensals
what are bacterial enzymes that coagulate plasma and are involved in abcess formation
coagulases
what species produce coagulases
some staphylococci species
coagulase tests are used to
differentiate between coagulase positive (s. aureus) and coagulative negative (s. epidermis)
is s. aureus coagulase positive or negative?
positive
is s. epidermis positive or negative?
negative
how does coagulase work
it binds plasma fibrinogen causing a clot in the plasma to gorm
what is a serological test designed to detect the presence of antibodies for specific microbial antigens in serum
agglutination
what type of antibiotics are administered based on laboratory results - when the organism is identified
therapeutic
what bacteria is a lactose fermenter
e coli
what bacteria are non lactose fermenters
p aeruginosa, salmonella
what bacteria are mannitol fermenters
s aureus
what bacteria are non mannitol fermenters
s epidermis
the primary causes of a urinary tract infection are
staphylococci , e coli and pseudomonas
bacterial antigens are categorized into 3 broad types based on their origin
o, h, k
o antigens are derived from
cell wall of gram negative bacteria
h antigens are derived from
flagella of motile enteric bacilli
k antigens are derived from
surface antigen secreted by the organism
E coli O157 causes
severe gastroenteritis
salmonella O D9-12 causes
typohoid fever
agglutination test is useful in detecting _____ carriers who harbor the bacteria but are asymptomatic
salmonella
