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
characteristics of endospores
- more resistant to heat stress
- contain calcium dipicolinate
- produced by bacillus
- macromolecules less susceptible to denaturation
chem agents and use
- chlorine — water pathogens
- ethylene oxide – plastic petri dishes
- sterilant – surgical equip
- sanitizers – cooking equipment
not: disinfectants– applied to skin before surgery
positive oxidase test, organism has
cytochrome c
elevated temp kills microorganism bc of
enzyme denaturing
protein unfolding
loss of DNA structur
function of durham tube
collect gas produced by fermentation
bacterial cells that have phage DNA integrated into their DNA
lysogens
MacConkey 24 hrs 37c, red colonies
gram -, ferments lactose
characteristics of streptococcus
- facultative anaerobe
- gram +
- chains
- spherical
doesn’t produce catalase
disinfectants
chem agents applied to inanimate objects to kill microorganisms
of bacteria/mL of an original culture if you transferred 1 mL of culture into 99 mL of sterile water and add .1 mL to agar and get 265 colonies
2.65x10^5
enteric bacteria
- faculatative anaerobes
- gram -
- rods
- in intestines
not spore former
distinguishing factor that strep are separated into by lancefield groups
amount of hemolysis
former name of HAIs
nosocomial infections
spectrophotometer is used to measure optical density , measurement of
turbidity
organism correctly matched with metabolism relationship to oxygen
aerotolerant – only ferments
in order to replicate a virus will
hijack host machinery
indole
cleavage product of tryptophan
nose swab, streak on mannitol salt agar, reddish
cannot ferment mannitol
T/F: thermal death time is the lowest temperature at which a population of a target organism is killed in 10 minutes
f
you dilute 1 ml from a 10 ml starter culture into 99 ml of liquid, total dilution is
10^-2A
gram -, coccus, oxidase +
neisseria
viral structure that contains genome
nucleocapsid
tsi slant, fermentation
red to yellow
characteristics of staph
halotolerant
- gram +
- non-spore forming
- part of human microbiota
not motile
zone of inhibition
diameter, in mm
positive oxidase test
reagent turns purple on end of swab
