Portage Microbiology Exam #5 2025 Update
COMPREHENSIVE FREQUENTLY TESTED QUESTIONS
and verified answers WITH RATIONALES| accurate
answers|100% solved!!
Define the concept of universal precautions (short answer) - (ANSWER)Universal
precautions means any and all samples, whether known or unknown, are to be
treated as potentially hazardous (or pathogenic) materials
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
Define commensal bacteria (short answer) (know term and definition first) -
(ANSWER)The bacterium neither harms nor benefits from the host from which it
obtains nutrients
COMPREHENSIVE FREQUENTLY TESTED QUESTIONS
and verified answers WITH RATIONALES| accurate
answers|100% solved!!
Define the concept of universal precautions (short answer) - (ANSWER)Universal
precautions means any and all samples, whether known or unknown, are to be
treated as potentially hazardous (or pathogenic) materials
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
Define commensal bacteria (short answer) (know term and definition first) -
(ANSWER)The bacterium neither harms nor benefits from the host from which it
obtains nutrients
