what are the three types of hemolysis breakdown?
alpha hemolysis - partial breakdown
beta hemolysis - complete breakdown
gamma hemolysis - no breakdown
alpha hemolysis is also called ‘[..] alpha’ due to having a [..] pigment when held up to light
green
green-ish
alpha hemolysis is partial breakdown think of geen for
beta hemolysis causes [..] to the media
clearing
due to it completing a complete breakdown it causes a clearing around the organism
gamma hemolysis appears similar to [..], change [..] a little bit
before
color
what is the organism that had no change on the blood agar plate
staphylococcus epidermidis, steptococcus pyogene, steptococcus pneumoniae
staphylococcus epidermidis
think of epidermidis as skin so no change = no change is gamma
gamma, no breakdown of RBC
which organism appeared for gamma hemolysis
staphylococcus epidermidis, steptococcus pneumoniae, steptococcus pyogene
staphylococcus epidermidis
gamma is no change
which organism appeared for the alpha hemolysis
staphylococcus epidermidis, steptococcus pneuomoniae, steptococcus pyogenes
steptococcus pneumoniae
alpha = green tint = sickness = pneumoniae
had greenish tint aka alpha hemolysis, partial breakdown of RBC’s
which organism had a greenish tint
staphylococcus epidermidis, steptococcus pneuomoniae, steptococcis pyogenes
steptococcus pneumoniae
think of pneumoniae as sickness = green = alpha greenish tint
green = alpha (aura) = partial breakdown
which organism showed clear on the blood agar plate
staphylococcus epidermidis, steptococcus pyogenes, steptococcus pneuomoniae
steptococcus pyogenes
pyogenes = genes = clear b/c not visisble to eye = beta clear
beta, complete breakdown of RBC
which organism appeared for beta hemolysis
steptococcus pyogene
beta = clear/ complete = genes not eye visible = pyogene
is the mac conkey agar plate and the mannitol salt agar plates, either differential or selective?
both
what does it mean when an agar plate is selective?
selecting for the growth of a certain group of organisms by inhibiting others
inhibiting is slowing down others or stopping them
what is the mannitol salt agar plate selective for
salt tolerant organisms
salt is for selective, differential for mannitol fermentation
the mannitol salt agar plate media is made of [..]% of NaCl conc. (concentration)
7.5%
what is the mannitol salt agar media plate differential for
mannitol fermentation
just like in the name it differentiates for mannitol fermentation
selective for salt and mannitol for differential
what is the process for mannitol fermentation
PLUNOL RED pH indicator, with acid fermentation, the pH drops, and the media turns YELLOW
differentials include a pH indicator, with acid fermentation, the pH dropping, and the growth turning a color.
since the mannitol salt agar plate consists of salt, do organisms thrive in salty environements
alot of organisms are unable to survive in a salty environment because it dehydratesthe cell. however, there are some organisms that can; e.g. organisms that can survive on our skin
the agar will SELECTIVELY grow organisms that can grow in salty environ.
how is the mannitol salt agar plate differential
thanks to its visual component of turning uellow when the pH drops
what is the mac conkey agar plate selective for
for the growth of gram negative organisms
since selective the media contains crystal violet and bile salts that INHIBIT gram positive growth
what does the mac conkey agar plate consist of
crystal violet and bile salts
what is the mac conkey agar plate differential for
lactose fermentation
what are the steps for the differential steps in the mac conkey agar plate?
NEUTRAL RED pH indicator, with acid fermentation, the pH drops, and the growth & media forms HOT PINK
what will the visual componenet of turning hot pink in the mac conkey agar plate tell us ?
if the organism is capable of fermentatino or not (lactose fermentation)
what are colliforms?
if the organism is gram-negative and can ferment lactose
