Bio Final Flashcards
positive coagulase test
solid clot
gram negative rod
e. coli, B meg
K/K reaction on lactose slant
no sugar fermented
bacteriostatic
inhibits growths of microbes, doesn’t kill them
indole positive, gram -, green metallic colonies on EMB
E coli
plaque forming units
4.5 x 10^7
blood agar plate, partial breakdown of hemoglobin in RBC –> greenish discoloration, what type of hemolysis
alpha
antiseptic
- alcohol
- betadine
- inhibits microbial growth
- kills microorganisms
doesn’t damage living tissue
coag positive, catalase positive, gram positive
s aureus
positive methyl red
red
MacConkey agar selective for ___ and differential for ___
lactose fermentation
barritts A and B associated with
voges proskauer test
downside of assessing bacterial cultures by turbidometric method
non viable cells are indistinguishable form viable
bacteriophage are viruses that infect bacterial cells
components:
- head
- capsid
- sheath
- tail
on a tsi slant hydrogen sulfids production would be indicated by ___ precipitate
black
T/F: s aureus produces a hemolysin called alpha toxin that causes a wide clear zone of beta hemolysis on blood agar
true
positive catalase test
bubbling after addition of reagent to cells
steps of lytic phage infection
- recognition
- penetration
- replication
- release
ingredient in MacConkey that makes it selective
bile salts, crystal violet
method used to test antimicrobial sensitivity of microorganisms
kirby bauer
(gamma) y-hemolysis on a blood agar plate =
no clearing
which is true ABOUT thermal death point
thermal death point is the lowest temperature at which a population of an organism is killed
characteristics of bacteriophage
- Teven phages infect e coli
- nucleic acid is encased in protein capsid
- they exhibit specificity to hosts
- obligate intracellular parasites
-dont: contain metabolic machinery
what does enzyme catalase do
breaks down toxic H2O2
