MICRO LAB TEST 3 (2025) LATEST
QUESTIONS & ANSWERS SCORED
A+
1 of 54
Term
7-3
The Mueller-Hinton II plates are supposed to be used within a specific
time after their preparation and should be free of visible
moisture. What negative effect(s) might moisture have on the test?
Give this one a try later!
this is a positive control
its main purpose is to verify that the hydrogen peroxide hasn't deteriorated
, into oxygen and water. To a lesser extent, it shows novice microbiologists what
"bubbling" looks like.
The purpose was to determine if the antibiotic is bacteriostatic (which should
result in growth on the TSA or NA plate) or bactericidal (which should show no
growth on the TSA or NA plate).
The older the plates, the drier they become. This could affect the ability
of the antibiotic to diffuse through the agar. Moisture will cause the
antibiotic to spread more rapidly.
The cells divide as time passes. What was equivalent to a 0.5 McFarland
standard may be considerably moire dense after 30 minutes.
Don't know?
2 of 54
Term
5-14
Why is the uninoculated control relatively unnecessary in this test?
Give this one a try later!
Aminopeptidases are enzymes that remove amio acids from the amino end of
proteins. These amino acids can then be used by the cell during its own protein
synthesis, or they can enter a catabolic pathway and be used in ATP production.
, The longer the exposure, the greater the damage and the less likely the cells can
repair the damage. Plates 1 and 3 should be compared, the only difference
between them is that they were exposed for different times
Usually there is plenty of medium that is not cleared (provided it is
not incubated for too long) to illustrate "no reaction" even when a
specific sector of the plate is not designated as the uninoculated
control.
This would affect the distance the antibiotic diffuses from the disk. The thicker
the agar, the more downward diffusion there is and the less antibiotic available
to diffuse outward. Thus, the zone would be smaller.
Don't know?
3 of 54
Definition
The easiest use of the garments would be to convert the nucleotides
into their triphosphate form and incorporate them into the cell's
DNA during its next round of replication. While not show,
deoxyribose can be converted into ribose and used to make
ribonucleotides. Deoxyribose, purines, and pyrimidines, can also be
used as energy sources in catabolic pathways, such as glycolysis and
the citric acid cycle.
Give this one a try later!
, 4-4
Is MSA a defined or undefined 4-4
medium? Provide reasoning behind In your own words, what is the
the your choice. application (purpose) of MSA?
5-14 4-4
In what ways can DNase (=) In your own words, what are the
organism use the products of roles of mannitol and phenol red in
DNA hydrolysis? MSA?
Don't know?
4 of 54
Definition
Even healthy throats may carry pathogens, but their numbers are too
small to create an infection (otherwise we wouldn't have
characterized the throats as "healthy") However, after incubation,
their numbers are greatly increased and pose a great threat for
infection of people in the lab.
Give this one a try later!
5-6
When flavoprotein transfers electrons directly to oxygen, hydrogen peroxide is
produced. What other consequences might result from electron carriers in the
ETC being bypassed?
5-6
Consider the step in the tube test where hydrogen peroxide is added to the
uninoculated tube.
QUESTIONS & ANSWERS SCORED
A+
1 of 54
Term
7-3
The Mueller-Hinton II plates are supposed to be used within a specific
time after their preparation and should be free of visible
moisture. What negative effect(s) might moisture have on the test?
Give this one a try later!
this is a positive control
its main purpose is to verify that the hydrogen peroxide hasn't deteriorated
, into oxygen and water. To a lesser extent, it shows novice microbiologists what
"bubbling" looks like.
The purpose was to determine if the antibiotic is bacteriostatic (which should
result in growth on the TSA or NA plate) or bactericidal (which should show no
growth on the TSA or NA plate).
The older the plates, the drier they become. This could affect the ability
of the antibiotic to diffuse through the agar. Moisture will cause the
antibiotic to spread more rapidly.
The cells divide as time passes. What was equivalent to a 0.5 McFarland
standard may be considerably moire dense after 30 minutes.
Don't know?
2 of 54
Term
5-14
Why is the uninoculated control relatively unnecessary in this test?
Give this one a try later!
Aminopeptidases are enzymes that remove amio acids from the amino end of
proteins. These amino acids can then be used by the cell during its own protein
synthesis, or they can enter a catabolic pathway and be used in ATP production.
, The longer the exposure, the greater the damage and the less likely the cells can
repair the damage. Plates 1 and 3 should be compared, the only difference
between them is that they were exposed for different times
Usually there is plenty of medium that is not cleared (provided it is
not incubated for too long) to illustrate "no reaction" even when a
specific sector of the plate is not designated as the uninoculated
control.
This would affect the distance the antibiotic diffuses from the disk. The thicker
the agar, the more downward diffusion there is and the less antibiotic available
to diffuse outward. Thus, the zone would be smaller.
Don't know?
3 of 54
Definition
The easiest use of the garments would be to convert the nucleotides
into their triphosphate form and incorporate them into the cell's
DNA during its next round of replication. While not show,
deoxyribose can be converted into ribose and used to make
ribonucleotides. Deoxyribose, purines, and pyrimidines, can also be
used as energy sources in catabolic pathways, such as glycolysis and
the citric acid cycle.
Give this one a try later!
, 4-4
Is MSA a defined or undefined 4-4
medium? Provide reasoning behind In your own words, what is the
the your choice. application (purpose) of MSA?
5-14 4-4
In what ways can DNase (=) In your own words, what are the
organism use the products of roles of mannitol and phenol red in
DNA hydrolysis? MSA?
Don't know?
4 of 54
Definition
Even healthy throats may carry pathogens, but their numbers are too
small to create an infection (otherwise we wouldn't have
characterized the throats as "healthy") However, after incubation,
their numbers are greatly increased and pose a great threat for
infection of people in the lab.
Give this one a try later!
5-6
When flavoprotein transfers electrons directly to oxygen, hydrogen peroxide is
produced. What other consequences might result from electron carriers in the
ETC being bypassed?
5-6
Consider the step in the tube test where hydrogen peroxide is added to the
uninoculated tube.
