PORTAGE LEARNING MICROBIOLOGY MODULE
5 STUDY QUESTIONS AND ANSWERS 2022
◉ List at lease 3 observations a researcher would be sure to note
while assessing and unknown microbial sample (short answer)
Answer: Need to note:
1. Size and shape
2. Any observable motility
3. Gram status (positive or negative)
◉ While observing an unknown sample of limited amounts, a
researcher must determine the following observations: 1) the
presence of any motility and 2) its Gram status using the same
sample- the liquid sample cannot be divided. Which would you
determine first and why? (short answer) Answer: You must
determine motility before determining Gram status. Motility
requires a wet mount, while gram staining requires heat fixing the
sample. If one were to begin with the gram stain, the heat fixation
process would kill the organism, making any observations regarding
motility impossible. The correct approach would be to place the
liquid culture on a glass slide and determine its motility status. Next,
the same liquid culture can be heat fixed and gram stained.
◉ A facultative anaerobe is a microorganism capable of growth
under what conditions? (short answer) Answer: A facultative
, anaerobe is capable of growth under aerobic (with oxygen) and
anaerobic (without oxygen) conditions
◉ True or False: The Lancefield groups are used to subdivide
antigenic groups of alpha-hemolytic Streptococcus Answer: False.
The Lancefield groups are used to subdivide beta-hemolytic strep
◉ The distinctions for Lancefield subgroups lie in its: (select all that
apply)
A. Catalase activity
B. Carbohydrate composition of antigens
C. Hemolytic activity
D. All of the above Answer: B. Carbohydrate composition of antigens
◉ Rheumatic fever displays _____ hemolytic activity and occurs when
_____ if left untreated Answer: Beta: strep. Pharyngitis
◉ True or False: Under most circumstances, staphylococcus can be
found in ~80% of human population where it remains non-
symptomatic Answer: False. Staphylococcus in only found (non-
symptomatic) in ~30% of the human population
5 STUDY QUESTIONS AND ANSWERS 2022
◉ List at lease 3 observations a researcher would be sure to note
while assessing and unknown microbial sample (short answer)
Answer: Need to note:
1. Size and shape
2. Any observable motility
3. Gram status (positive or negative)
◉ While observing an unknown sample of limited amounts, a
researcher must determine the following observations: 1) the
presence of any motility and 2) its Gram status using the same
sample- the liquid sample cannot be divided. Which would you
determine first and why? (short answer) Answer: You must
determine motility before determining Gram status. Motility
requires a wet mount, while gram staining requires heat fixing the
sample. If one were to begin with the gram stain, the heat fixation
process would kill the organism, making any observations regarding
motility impossible. The correct approach would be to place the
liquid culture on a glass slide and determine its motility status. Next,
the same liquid culture can be heat fixed and gram stained.
◉ A facultative anaerobe is a microorganism capable of growth
under what conditions? (short answer) Answer: A facultative
, anaerobe is capable of growth under aerobic (with oxygen) and
anaerobic (without oxygen) conditions
◉ True or False: The Lancefield groups are used to subdivide
antigenic groups of alpha-hemolytic Streptococcus Answer: False.
The Lancefield groups are used to subdivide beta-hemolytic strep
◉ The distinctions for Lancefield subgroups lie in its: (select all that
apply)
A. Catalase activity
B. Carbohydrate composition of antigens
C. Hemolytic activity
D. All of the above Answer: B. Carbohydrate composition of antigens
◉ Rheumatic fever displays _____ hemolytic activity and occurs when
_____ if left untreated Answer: Beta: strep. Pharyngitis
◉ True or False: Under most circumstances, staphylococcus can be
found in ~80% of human population where it remains non-
symptomatic Answer: False. Staphylococcus in only found (non-
symptomatic) in ~30% of the human population
