General Microbiology Lab Exam Review Questions
with Correct Answers 2026 Update
Aseptic - CORRECT ANSWER -means "without microorganisms"
Aseptic Technique - CORRECT ANSWER --refers to practices that help reduce the risk of
microbial exposure, transmission, and contamination
-some practices are also designed to reduce service providers' risk of exposure to potentially
infectious blood and tissue during clinical procedures
-remove or kill microorganisms from hands and objects, reducing the risk of transfer of potential
pathogens
-employ sterile instruments and other items. reduce clients' risk of exposure to microorganisms
that cannot be removed
Bacteria is measured in - CORRECT ANSWER -Microns
The majority of bacteria are either - CORRECT ANSWER -spheres (cocci) or rods (bacilli)
-a few occur as curved rods (vibrios)
The shape and arrangement of cells with their staining properties are used for - CORRECT
ANSWER -classifying and preliminarily identifying clinical isolates
The most commonly used stain - CORRECT ANSWER -Gram stain
Selective Media - CORRECT ANSWER --culture media which select for growth of groups of
organisms
-restricted to situations where an ingredient is added which allows the growth of a particular
organism, while inhibiting to a considerable extent the growth of other organisms which might
be found in the same environment
, -examples include
MacConkey agar
Thayer-Martin agar
Mannitol Salt agar
Growth Media - CORRECT ANSWER -used to culture microbes
Artificial culture media - CORRECT ANSWER -made up of agar (solid) or a special liquid (broth)
which contain necessary nutrients to grow a variety of bacteria and fungi
-viruses will not grow on this type of media
Cell or Tissue culture media - CORRECT ANSWER -contains living cells/ tissues which act like
"host" cells in order to row and study viruses and other obligate intracellular organisms
Broths - CORRECT ANSWER -liquid media that become turbid as bacteria grow
Turbidity - CORRECT ANSWER -refers to the change that occurs in both as bacteria grow - the
more bacteria grow, the more they increase the cloudiness of the broth, changing it from the
original clear to a "dirty" appearance
Agar slant or "slant" - CORRECT ANSWER -agar (with a texture much like firm gelatin, but made
from seaweed) is poured into a test tube and allowed to solidify so that the agar surface in the
test tube is slanted. It is on this surface that bacteria grow. Often, long term (4-6 weeks) storage
of bacterial cultures is done using this format.
Agar plates - CORRECT ANSWER -agar is poured into a petri dish and allowed to solidify. This
produces a relatively large flat surface for bacterial growth and isolation
with Correct Answers 2026 Update
Aseptic - CORRECT ANSWER -means "without microorganisms"
Aseptic Technique - CORRECT ANSWER --refers to practices that help reduce the risk of
microbial exposure, transmission, and contamination
-some practices are also designed to reduce service providers' risk of exposure to potentially
infectious blood and tissue during clinical procedures
-remove or kill microorganisms from hands and objects, reducing the risk of transfer of potential
pathogens
-employ sterile instruments and other items. reduce clients' risk of exposure to microorganisms
that cannot be removed
Bacteria is measured in - CORRECT ANSWER -Microns
The majority of bacteria are either - CORRECT ANSWER -spheres (cocci) or rods (bacilli)
-a few occur as curved rods (vibrios)
The shape and arrangement of cells with their staining properties are used for - CORRECT
ANSWER -classifying and preliminarily identifying clinical isolates
The most commonly used stain - CORRECT ANSWER -Gram stain
Selective Media - CORRECT ANSWER --culture media which select for growth of groups of
organisms
-restricted to situations where an ingredient is added which allows the growth of a particular
organism, while inhibiting to a considerable extent the growth of other organisms which might
be found in the same environment
, -examples include
MacConkey agar
Thayer-Martin agar
Mannitol Salt agar
Growth Media - CORRECT ANSWER -used to culture microbes
Artificial culture media - CORRECT ANSWER -made up of agar (solid) or a special liquid (broth)
which contain necessary nutrients to grow a variety of bacteria and fungi
-viruses will not grow on this type of media
Cell or Tissue culture media - CORRECT ANSWER -contains living cells/ tissues which act like
"host" cells in order to row and study viruses and other obligate intracellular organisms
Broths - CORRECT ANSWER -liquid media that become turbid as bacteria grow
Turbidity - CORRECT ANSWER -refers to the change that occurs in both as bacteria grow - the
more bacteria grow, the more they increase the cloudiness of the broth, changing it from the
original clear to a "dirty" appearance
Agar slant or "slant" - CORRECT ANSWER -agar (with a texture much like firm gelatin, but made
from seaweed) is poured into a test tube and allowed to solidify so that the agar surface in the
test tube is slanted. It is on this surface that bacteria grow. Often, long term (4-6 weeks) storage
of bacterial cultures is done using this format.
Agar plates - CORRECT ANSWER -agar is poured into a petri dish and allowed to solidify. This
produces a relatively large flat surface for bacterial growth and isolation
