2025-2026 SERIES
TCU MICROBIOLOGY LAB EXAM 1 COMPLETE
QUESTIONS AND CORRECT ANSWERS | GRADED
AND THE LATEST SERIES
chemically defined (synthetic) media
Ans: media composed of precisely defined chemicals
Question: elements that all bacteria need
Ans: carbon, nitrogen, phosphorus, sulfur, oxygen, and hydrogen
Question: minimal media
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
Question: complex media
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
Question: enriched media
, 2025-2026 SERIES
Ans: complex media that contains additional "special" nutrients/additives that
are not commonly found in media
- least commonly used media
Question: autoclave
Ans: media is subjected to high-pressure steam at 121C at 15 lbs. of pressure to
sterilize and destroy any contaminants present
Question: two major forms of media
Ans: liquid and solid media
- media solidifies by adding agar (1.5%)
- agar is inert and incapable of growing by itself
Question: what temperature do most bacterial organisms grow at?
Ans: 37C (98.6F)
Question: colony
Ans: A population of cells arising from a bacterial cell group or from a group of
attached bacterial cells
Question: colony forming units (cfu)
Ans: estimate the approximate number of bacteria in a liquid broth culture
Question: simple microscope
, 2025-2026 SERIES
Ans: contains a single magnifying lens and is similar to a magnifying lens
Question: compound microscope
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
Question: illuminator
Ans: light emits from this
Question: condenser
Ans: light passes through this and concentrates the light and focuses the light onto
the specimen
Question: parfocal
Ans: property of a microscope which allows objectives to be changed with
minimal or no refocusing
Question: total magnification
Ans: objective magnification (4X, 10X, 40X, 100X) x ocular magnification (10X)
Question: working distance
Ans: distance between the objective and the object being viewed
Question: depth of focus
TCU MICROBIOLOGY LAB EXAM 1 COMPLETE
QUESTIONS AND CORRECT ANSWERS | GRADED
AND THE LATEST SERIES
chemically defined (synthetic) media
Ans: media composed of precisely defined chemicals
Question: elements that all bacteria need
Ans: carbon, nitrogen, phosphorus, sulfur, oxygen, and hydrogen
Question: minimal media
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
Question: complex media
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
Question: enriched media
, 2025-2026 SERIES
Ans: complex media that contains additional "special" nutrients/additives that
are not commonly found in media
- least commonly used media
Question: autoclave
Ans: media is subjected to high-pressure steam at 121C at 15 lbs. of pressure to
sterilize and destroy any contaminants present
Question: two major forms of media
Ans: liquid and solid media
- media solidifies by adding agar (1.5%)
- agar is inert and incapable of growing by itself
Question: what temperature do most bacterial organisms grow at?
Ans: 37C (98.6F)
Question: colony
Ans: A population of cells arising from a bacterial cell group or from a group of
attached bacterial cells
Question: colony forming units (cfu)
Ans: estimate the approximate number of bacteria in a liquid broth culture
Question: simple microscope
, 2025-2026 SERIES
Ans: contains a single magnifying lens and is similar to a magnifying lens
Question: compound microscope
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
Question: illuminator
Ans: light emits from this
Question: condenser
Ans: light passes through this and concentrates the light and focuses the light onto
the specimen
Question: parfocal
Ans: property of a microscope which allows objectives to be changed with
minimal or no refocusing
Question: total magnification
Ans: objective magnification (4X, 10X, 40X, 100X) x ocular magnification (10X)
Question: working distance
Ans: distance between the objective and the object being viewed
Question: depth of focus
