MT AAB Study Guide Quizlet Exam 2025
With 100% Correct Answers
What term describes the morphology of organisms that vary in shape and size? - correct
answers ✔✔Pleomorphic
i.e. coccobacilli
Bacteriology arrangements: - correct answers ✔✔-pairs (diplococci "N. Gon"; diplobacilli
-chains (streptococci, streptobacilli)
-grape like clusters (staphylococci)
-group of four-tetrads (peptococcus)
-packets of eight-cuboidal (sarcina)
-palisades (corneybacterium)
Capsules are the basis of which test? - correct answers ✔✔serotyping
and identification (capsules are antigenic); they are observed using India ink (negative staining)
representative organisms (Strep pneumo, Kleb pneumo, Haemophilus influenza, and Neisseria
meningitidius)
A mucoid colony on blood agar medium indicates that which of the following characteristics
may be present? - correct answers ✔✔Organism has a capsule.
-it surrounds some bacteria
,What are dark staining granules called? - correct answers ✔✔Metachromatic granunles
-affinity for basic dyes
-stains such as Albert, Neisser, and methylene blue
Which of the following organisms are non-motile? - correct answers ✔✔Shigella and Klebsiella
(with exception to Salmonella--other "ella" are nonmotile)
Shigella (neg) vs Salmonella (pos)
Klebsiella (neg) vs Enterobacter (pos)
Bacillus anthracis (neg) vs most bacillus species (pos) best observed at 25C
35-37C ,au be inhibitory
In the bacterial growth cycle, growth ceases because nutrients are exhausted or toxic metabolic
products have accumulated in which phase? - correct answers ✔✔Stationary phase
(plateau ceases-nutrients exhausted/toxic)
Which of the following genera of bacteria form spores? - correct answers ✔✔Bacillus and
Clostridium
endospores-non feeding, non motile, non reproductive
-highly resistant to heat, drying, freezing; toxic chemical & radiation.
(Sporulating bacteria-bacteria in which spores are forming)
,What term is used to describe bacteria that grow in the absence of atmospheric oxygen and
obtain oxygen from oxygen-containing compounds? - correct answers ✔✔Anaerobes
Aerobes - correct answers ✔✔grows in presence of (free) O2
Capnophiles - correct answers ✔✔growth enhanced by increased CO2
aerotolerants - correct answers ✔✔does not grow well but tolerate (survive) in presence of
oxygen
What is the temperature at which bacteria grow best known as? - correct answers ✔✔Optimum
mesophilic - correct answers ✔✔grows best 35-37C; most organisms will grow at 20C
thermophilic - correct answers ✔✔heat loving (50*55C); autoclaving procedures
psychotrophilic - correct answers ✔✔cold loving (10C)-blood bank contaminancts
On blood agar plates a small zone of alpha hemolysis surrounded by a zone of beta hemolysis
after refrigeration is known as what type of hemolysis? - correct answers ✔✔Alpha-prime
hemolysis
-Beta hemolysis (clear, colorless-complete hemolysis)
-alpa hemolysis (green, incomplete hemolysis)
-Gamma hemolysis (no hemolysis)
, What is the most effective method of sterilization? - correct answers ✔✔Autoclaving (steam at
121C @ 16 lbs pressure for 15-30 min)-**QC Bacillus STEAROTHERMOPHILUS
-boiling method (kills all veg-not all spores/viruses (100C for 15-30 min)
Under Fractional Sterilization (used to sterilize media containing mile or serum)
-alternate heating which kills vegetative cells, followed by incubation when spores germinate,
followed by heating, which kills the remaining
tyndallization-flowing steam for 30 min on 3 successive days
-inspissation-75-80C for 2 hrs on 3 successive days
Which of the following is used for quality control for the dry heat oven? - correct answers
✔✔Bacillus subtilis
Dry Heat method
-kills by oxidation
-oven 160-180C for 1-2 hours
-QUALITY CONTROLS (Bacillus Subtilis)
Media that cannot be heated can be sterilized by what alternate method? - correct answers
✔✔Filtration
asbestos filter-98% effective
membrane filter-0.22 micron = 100% bacterial sterility
for media that are degraded by heat;
Which one of the following disinfectants is the most effective germicide against bacteria, spores,
tubercle bacilli, fungi, and viruses? - correct answers ✔✔Chlorine (bleach)
With 100% Correct Answers
What term describes the morphology of organisms that vary in shape and size? - correct
answers ✔✔Pleomorphic
i.e. coccobacilli
Bacteriology arrangements: - correct answers ✔✔-pairs (diplococci "N. Gon"; diplobacilli
-chains (streptococci, streptobacilli)
-grape like clusters (staphylococci)
-group of four-tetrads (peptococcus)
-packets of eight-cuboidal (sarcina)
-palisades (corneybacterium)
Capsules are the basis of which test? - correct answers ✔✔serotyping
and identification (capsules are antigenic); they are observed using India ink (negative staining)
representative organisms (Strep pneumo, Kleb pneumo, Haemophilus influenza, and Neisseria
meningitidius)
A mucoid colony on blood agar medium indicates that which of the following characteristics
may be present? - correct answers ✔✔Organism has a capsule.
-it surrounds some bacteria
,What are dark staining granules called? - correct answers ✔✔Metachromatic granunles
-affinity for basic dyes
-stains such as Albert, Neisser, and methylene blue
Which of the following organisms are non-motile? - correct answers ✔✔Shigella and Klebsiella
(with exception to Salmonella--other "ella" are nonmotile)
Shigella (neg) vs Salmonella (pos)
Klebsiella (neg) vs Enterobacter (pos)
Bacillus anthracis (neg) vs most bacillus species (pos) best observed at 25C
35-37C ,au be inhibitory
In the bacterial growth cycle, growth ceases because nutrients are exhausted or toxic metabolic
products have accumulated in which phase? - correct answers ✔✔Stationary phase
(plateau ceases-nutrients exhausted/toxic)
Which of the following genera of bacteria form spores? - correct answers ✔✔Bacillus and
Clostridium
endospores-non feeding, non motile, non reproductive
-highly resistant to heat, drying, freezing; toxic chemical & radiation.
(Sporulating bacteria-bacteria in which spores are forming)
,What term is used to describe bacteria that grow in the absence of atmospheric oxygen and
obtain oxygen from oxygen-containing compounds? - correct answers ✔✔Anaerobes
Aerobes - correct answers ✔✔grows in presence of (free) O2
Capnophiles - correct answers ✔✔growth enhanced by increased CO2
aerotolerants - correct answers ✔✔does not grow well but tolerate (survive) in presence of
oxygen
What is the temperature at which bacteria grow best known as? - correct answers ✔✔Optimum
mesophilic - correct answers ✔✔grows best 35-37C; most organisms will grow at 20C
thermophilic - correct answers ✔✔heat loving (50*55C); autoclaving procedures
psychotrophilic - correct answers ✔✔cold loving (10C)-blood bank contaminancts
On blood agar plates a small zone of alpha hemolysis surrounded by a zone of beta hemolysis
after refrigeration is known as what type of hemolysis? - correct answers ✔✔Alpha-prime
hemolysis
-Beta hemolysis (clear, colorless-complete hemolysis)
-alpa hemolysis (green, incomplete hemolysis)
-Gamma hemolysis (no hemolysis)
, What is the most effective method of sterilization? - correct answers ✔✔Autoclaving (steam at
121C @ 16 lbs pressure for 15-30 min)-**QC Bacillus STEAROTHERMOPHILUS
-boiling method (kills all veg-not all spores/viruses (100C for 15-30 min)
Under Fractional Sterilization (used to sterilize media containing mile or serum)
-alternate heating which kills vegetative cells, followed by incubation when spores germinate,
followed by heating, which kills the remaining
tyndallization-flowing steam for 30 min on 3 successive days
-inspissation-75-80C for 2 hrs on 3 successive days
Which of the following is used for quality control for the dry heat oven? - correct answers
✔✔Bacillus subtilis
Dry Heat method
-kills by oxidation
-oven 160-180C for 1-2 hours
-QUALITY CONTROLS (Bacillus Subtilis)
Media that cannot be heated can be sterilized by what alternate method? - correct answers
✔✔Filtration
asbestos filter-98% effective
membrane filter-0.22 micron = 100% bacterial sterility
for media that are degraded by heat;
Which one of the following disinfectants is the most effective germicide against bacteria, spores,
tubercle bacilli, fungi, and viruses? - correct answers ✔✔Chlorine (bleach)
