quiz 3-3-15 Flashcards
what can be measured either quantitatively or qualitatively
bacterial growth
this device electronically counts cells as they pass through it
coulter counter
this device manually counts cells with a microscope and has a disadvantage not being able to discriminate between dead and alive cells
Petroff Hausser counting chamber
what is the method of counting bacteria in which you spread the bacteria on a plate with a sterile hockey stick and incubate it?
spread method
what is the method of counting bacteria in which you pour molten agar medium into a plate and the bacterial colonies grow inside and on top of the agar?
pour method
Bacteria divide by what method?
binary fission
what phase of growth is when the cells are metabolically active and not reproducing?
lag phase
what phase of growth is when the cells are reproducing at an exponential rate?
log phase
what phase of growth is when the cells reproduction is equal to the rate of the cells dying?
stationary phase
what phase of growth is when the cells are dying off at an exponential rate?
death phase
what it the time it takes for the population to double; which is genetically determined?
generation time
what is the gas requirement category for a microbe that cannot grow without oxygen?
obligate aerobe
what is the gas requirement category for a microbe that requires oxygen for its metabolism and is capable of growth in the absence of it?
facultative anaerobe
what is the gas requirement category for a microbe that does not grow at normal atmospheric concentrations of oxygen but requires a small amount of it ( 1-15%)?
microaerophile
what is the gas requirement category for a microbe that lacks the enzyme for processing toxic oxygen, they cannot tolerate only free oxygen, they do not use oxygen for respiration and are not able to grow in the presence of oxygen?
obligate anaerobe
what is the gas requirement category for a microbe that does not utilize oxygen but can survive and grow in its presents?
aerotolerant anaerobe
what is the gas requirement category for a microbe that grows best at higher carbon dioxide tensions (3-10%)?
capnophiles
what is the name of the medium that creates a reduced environment in the semi-soft agar, with a small amount of oxygen diffusing in from the top?
thioglycollate
what cell wall is 60-90% peptidoglycan?
gram +
what cell wall is 10-20% peptidoglycan?
gram -
which cell wall retains the primary dye?
gram +
which cell wall type does the decolorizer remove the primary dye?
gram -
which cell wall type picks up the counterstain?
gram-
which cell wall type has a lipopolysaccharide layer?
gram-
which cell wall type has teichoic acid and lipoteichoic acids?
gram +
what is the result that has both gram - and gram + results
gram variable
what would cause a gram variable result?
age of the culture
technique
genetics
medium
what is the result, in which the bacteria doesn’t pick up either the primary or the counterstain?
gram non reaction
what would cause a gram non reaction result?
waxy lipids in the cell wall
example: mycobacteria, norcardia, lepra
