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BIOL 351
BIOL 351 Module 2 (Latest Update ) Pharmacology |
Questions & Answers | Grade A | 100% Correct - Portage Learning
Question 1
A nurse is teaching about soil microbiology. The primary role of fungi in soil ecosystems
is as:
A. Pathogens
B. Symbionts
C. Saprophytes (decomposers of dead plant material)
D. Nitrogen fixers
CORRECT ANSWER: C. Saprophytes (decomposers of dead plant material)
Rationale: Fungi are primarily saprophytic, meaning they decompose dead organic
matter, recycling nutrients back into the ecosystem.
Question 2
A nursing student is preparing a serial dilution. Which description is accurate?
A. Each tube contains a different type of growth medium.
B. Each tube in the series contains a dilution of the sample from the previous tube.
BIOL 351
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BIOL 351
C. The sample is diluted only once in a large volume.
D. The dilution factor remains constant, but the diluent changes.
CORRECT ANSWER: B. Each tube in the series contains a dilution of the sample from
the previous tube.
Rationale: A serial dilution involves sequentially diluting a sample by transferring a small
volume into a larger volume of diluent, creating a logarithmic decrease in concentration
at each step.
Question 3
In a typical soil sample, which group of microorganisms is most abundant?
A. Fungi
B. Actinomycetes
C. Bacteria
D. Protozoa
CORRECT ANSWER: C. Bacteria
Rationale: Bacteria are the most numerous microorganisms in soil by cell count, playing
critical roles in nutrient cycling and organic matter decomposition.
Question 4
A nurse understands that actinomycetes in soil are important because they:
A. Cause most plant diseases.
BIOL 351
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BIOL 351
B. Are primary nitrogen fixers.
C. Are important organic matter decomposers and humus producers.
D. Predominantly cause human skin infections.
CORRECT ANSWER: C. Are important organic matter decomposers and humus
producers.
Rationale: Actinomycetes are filamentous bacteria crucial for breaking down complex
organic materials like cellulose and chitin, contributing to soil fertility and the
production of humus.
Question 5
Glycerol Yeast Agar (GYA) is selective for which group of microbes?
A. Gram-negative bacteria
B. Fungi
C. Actinomycetes
D. Coliforms
CORRECT ANSWER: C. Actinomycetes
Rationale: GYA has limited nutritive value, which inhibits the growth of many bacteria
and fungi, making it selective for slow-growing actinomycetes.
Question 6
BIOL 351
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BIOL 351
Nutrient Agar (similar to Tryptic Soy Agar) is best described as a medium that supports:
A. Only Gram-positive bacteria
B. A broad range of bacteria
C. Only fungi
D. Only anaerobic bacteria
CORRECT ANSWER: B. A broad range of bacteria
Rationale: Nutrient Agar is a general-purpose, non-selective medium containing
peptides and nutrients that support the growth of a wide variety of heterotrophic
bacteria.
Question 7
Sabouraud Dextrose Agar (SDA) is formulated to preferentially grow:
A. Bacteria
B. Fungi
C. Actinomycetes
D. Viruses
CORRECT ANSWER: B. Fungi
Rationale: SDA has a low pH (around 5.6) and high sugar content, which inhibits most
bacteria while promoting fungal growth. Antibiotics are often added to further suppress
bacterial contamination.
BIOL 351
BIOL 351
BIOL 351 Module 2 (Latest Update ) Pharmacology |
Questions & Answers | Grade A | 100% Correct - Portage Learning
Question 1
A nurse is teaching about soil microbiology. The primary role of fungi in soil ecosystems
is as:
A. Pathogens
B. Symbionts
C. Saprophytes (decomposers of dead plant material)
D. Nitrogen fixers
CORRECT ANSWER: C. Saprophytes (decomposers of dead plant material)
Rationale: Fungi are primarily saprophytic, meaning they decompose dead organic
matter, recycling nutrients back into the ecosystem.
Question 2
A nursing student is preparing a serial dilution. Which description is accurate?
A. Each tube contains a different type of growth medium.
B. Each tube in the series contains a dilution of the sample from the previous tube.
BIOL 351
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BIOL 351
C. The sample is diluted only once in a large volume.
D. The dilution factor remains constant, but the diluent changes.
CORRECT ANSWER: B. Each tube in the series contains a dilution of the sample from
the previous tube.
Rationale: A serial dilution involves sequentially diluting a sample by transferring a small
volume into a larger volume of diluent, creating a logarithmic decrease in concentration
at each step.
Question 3
In a typical soil sample, which group of microorganisms is most abundant?
A. Fungi
B. Actinomycetes
C. Bacteria
D. Protozoa
CORRECT ANSWER: C. Bacteria
Rationale: Bacteria are the most numerous microorganisms in soil by cell count, playing
critical roles in nutrient cycling and organic matter decomposition.
Question 4
A nurse understands that actinomycetes in soil are important because they:
A. Cause most plant diseases.
BIOL 351
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BIOL 351
B. Are primary nitrogen fixers.
C. Are important organic matter decomposers and humus producers.
D. Predominantly cause human skin infections.
CORRECT ANSWER: C. Are important organic matter decomposers and humus
producers.
Rationale: Actinomycetes are filamentous bacteria crucial for breaking down complex
organic materials like cellulose and chitin, contributing to soil fertility and the
production of humus.
Question 5
Glycerol Yeast Agar (GYA) is selective for which group of microbes?
A. Gram-negative bacteria
B. Fungi
C. Actinomycetes
D. Coliforms
CORRECT ANSWER: C. Actinomycetes
Rationale: GYA has limited nutritive value, which inhibits the growth of many bacteria
and fungi, making it selective for slow-growing actinomycetes.
Question 6
BIOL 351
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BIOL 351
Nutrient Agar (similar to Tryptic Soy Agar) is best described as a medium that supports:
A. Only Gram-positive bacteria
B. A broad range of bacteria
C. Only fungi
D. Only anaerobic bacteria
CORRECT ANSWER: B. A broad range of bacteria
Rationale: Nutrient Agar is a general-purpose, non-selective medium containing
peptides and nutrients that support the growth of a wide variety of heterotrophic
bacteria.
Question 7
Sabouraud Dextrose Agar (SDA) is formulated to preferentially grow:
A. Bacteria
B. Fungi
C. Actinomycetes
D. Viruses
CORRECT ANSWER: B. Fungi
Rationale: SDA has a low pH (around 5.6) and high sugar content, which inhibits most
bacteria while promoting fungal growth. Antibiotics are often added to further suppress
bacterial contamination.
BIOL 351
