TCU Microbiology Lab Exam 1 with
Verified Solutions
chemically defined (synthetic) media Correct Ans-media composed of precisely defined
chemicals
elements that all bacteria need Correct Ans-carbon, nitrogen, phosphorus, sulfur, oxygen, and
hydrogen
minimal media Correct Ans-media that contains exact nutrients needed for growth and
nothing extra
- media is useful b/c we know exactly what's in it, but few organisms are resourceful enough to
survive with only a few salts and sugars
complex media Correct Ans-- it contains all the nutrients necessary for the microbes
- aka general purpose media, satisfies the nutritional requirements of bacteria with more stringent
growth requirements
- consists of mix of digests & extracts from plant or animal tissue
- nutrient rich but poorly defined with the exact nutrients unknown
- in lab we use complex media: tryptic soy media
enriched media Correct Ans-complex media that contains additional "special"
nutrients/additives that are not commonly found in media
- least commonly used media
,autoclave Correct Ans-media is subjected to high-pressure steam at 121C at 15 lbs. of
pressure to sterilize and destroy any contaminants present
two major forms of media Correct Ans-liquid and solid media
- media solidifies by adding agar (1.5%)
- agar is inert and incapable of growing by itself
what temperature do most bacterial organisms grow at? Correct Ans-37C (98.6F)
colony Correct Ans-A population of cells arising from a bacterial cell group or from a group
of attached bacterial cells
colony forming units (cfu) Correct Ans-estimate the approximate number of bacteria in a
liquid broth culture
simple microscope Correct Ans-contains a single magnifying lens and is similar to a
magnifying lens
compound microscope Correct Ans-consists of two singles lenses arranged one in front of the
other so that the second lens magnifies the image produced by the first
illuminator Correct Ans-light emits from this
, condenser Correct Ans-light passes through this and concentrates the light and focuses the
light onto the specimen
parfocal Correct Ans-property of a microscope which allows objectives to be changed with
minimal or no refocusing
total magnification Correct Ans-objective magnification (4X, 10X, 40X, 100X) x ocular
magnification (10X)
working distance Correct Ans-distance between the objective and the object being viewed
depth of focus Correct Ans-thickness of specimen that can be seen in focus at one time
resolving power Correct Ans-the ability of the microscope to distinguish between two closely
adjacent points; measured in distance units
refractive index Correct Ans-measure of how much the speed of light is reduced inside a
medium such as glass; the refractive index of air and glass are different enough so that light
waves change direction when they cross the interface from air to glass. The necessitates that use
of immersion oil with our 100X oil-immersion oil.
aseptic technique Correct Ans-transferring without causing contamination to the culture
- minimizes the chance of infection
Verified Solutions
chemically defined (synthetic) media Correct Ans-media composed of precisely defined
chemicals
elements that all bacteria need Correct Ans-carbon, nitrogen, phosphorus, sulfur, oxygen, and
hydrogen
minimal media Correct Ans-media that contains exact nutrients needed for growth and
nothing extra
- media is useful b/c we know exactly what's in it, but few organisms are resourceful enough to
survive with only a few salts and sugars
complex media Correct Ans-- it contains all the nutrients necessary for the microbes
- aka general purpose media, satisfies the nutritional requirements of bacteria with more stringent
growth requirements
- consists of mix of digests & extracts from plant or animal tissue
- nutrient rich but poorly defined with the exact nutrients unknown
- in lab we use complex media: tryptic soy media
enriched media Correct Ans-complex media that contains additional "special"
nutrients/additives that are not commonly found in media
- least commonly used media
,autoclave Correct Ans-media is subjected to high-pressure steam at 121C at 15 lbs. of
pressure to sterilize and destroy any contaminants present
two major forms of media Correct Ans-liquid and solid media
- media solidifies by adding agar (1.5%)
- agar is inert and incapable of growing by itself
what temperature do most bacterial organisms grow at? Correct Ans-37C (98.6F)
colony Correct Ans-A population of cells arising from a bacterial cell group or from a group
of attached bacterial cells
colony forming units (cfu) Correct Ans-estimate the approximate number of bacteria in a
liquid broth culture
simple microscope Correct Ans-contains a single magnifying lens and is similar to a
magnifying lens
compound microscope Correct Ans-consists of two singles lenses arranged one in front of the
other so that the second lens magnifies the image produced by the first
illuminator Correct Ans-light emits from this
, condenser Correct Ans-light passes through this and concentrates the light and focuses the
light onto the specimen
parfocal Correct Ans-property of a microscope which allows objectives to be changed with
minimal or no refocusing
total magnification Correct Ans-objective magnification (4X, 10X, 40X, 100X) x ocular
magnification (10X)
working distance Correct Ans-distance between the objective and the object being viewed
depth of focus Correct Ans-thickness of specimen that can be seen in focus at one time
resolving power Correct Ans-the ability of the microscope to distinguish between two closely
adjacent points; measured in distance units
refractive index Correct Ans-measure of how much the speed of light is reduced inside a
medium such as glass; the refractive index of air and glass are different enough so that light
waves change direction when they cross the interface from air to glass. The necessitates that use
of immersion oil with our 100X oil-immersion oil.
aseptic technique Correct Ans-transferring without causing contamination to the culture
- minimizes the chance of infection
