bio 205 lab fi nal exam :
identifi cation of unk now n
bacter ia Questions and answ er s
w ith accur ate
r ationales(PASSED )
selective media - answer allows growth of certain organisms while inhibiting
others
examples of selective media - answer MAC, MSN, EMB
differential media - answer allows growth of multiple organisms but have
components that allow the researcher to differentiate between them
examples of differential media - answer MAC, MSN, EMB, Blood agar
MacKonkey Agar MAC - answer inhibits gram positive bacterial growth while
selecting for growth of gram negative bacteria
lactose fermentation - answer MAC differentiates between enteric bacteria based
on
pink - answer if e.coli is present on MAC, plates would turn
, EMB agar (eosin methylene blue) - answer inhibits growth of gram positive
bacteria. and encourages growth of gram negative bacteria
if the bacteria can ferment lactose or not - answer EMB differentiates between
gram negative enteric based on
blue - answer when lactose is fermented on EMB, the media turns
it will turn colonies blue with green metallic sheen due to large amounts of acid
produced that precipitates dyes onto surface - answer if e.coli is present on EMB
mannitol salt agar (MSA) - answer inhibits growth of most bacteria, but allows
growth of staphylococci bacteria
mannitol - answer in MSA, staphylococci can ferment
mannitol fermentation - answer MSA differentiates staphylococcal species based
on
yellow media (can ferment) - answer if staphylococcus aureus is present on MSA
pink (can not ferment) - answer if staphylococcus epidermis is present on MSA
hemolytic properties - answer blood agar differentiates b/w bacteria based on
identifi cation of unk now n
bacter ia Questions and answ er s
w ith accur ate
r ationales(PASSED )
selective media - answer allows growth of certain organisms while inhibiting
others
examples of selective media - answer MAC, MSN, EMB
differential media - answer allows growth of multiple organisms but have
components that allow the researcher to differentiate between them
examples of differential media - answer MAC, MSN, EMB, Blood agar
MacKonkey Agar MAC - answer inhibits gram positive bacterial growth while
selecting for growth of gram negative bacteria
lactose fermentation - answer MAC differentiates between enteric bacteria based
on
pink - answer if e.coli is present on MAC, plates would turn
, EMB agar (eosin methylene blue) - answer inhibits growth of gram positive
bacteria. and encourages growth of gram negative bacteria
if the bacteria can ferment lactose or not - answer EMB differentiates between
gram negative enteric based on
blue - answer when lactose is fermented on EMB, the media turns
it will turn colonies blue with green metallic sheen due to large amounts of acid
produced that precipitates dyes onto surface - answer if e.coli is present on EMB
mannitol salt agar (MSA) - answer inhibits growth of most bacteria, but allows
growth of staphylococci bacteria
mannitol - answer in MSA, staphylococci can ferment
mannitol fermentation - answer MSA differentiates staphylococcal species based
on
yellow media (can ferment) - answer if staphylococcus aureus is present on MSA
pink (can not ferment) - answer if staphylococcus epidermis is present on MSA
hemolytic properties - answer blood agar differentiates b/w bacteria based on
