WGU D311 MICROBIOLOGY REAL EXAM – VERIFIED
QUESTIONS, DETAILED ANSWERS & RATIONALES | PASS
WITH CONFIDENCE
Which statement describes prokaryotic cells?
a) Prokaryotic cells are found in coccus form in both pairs and clusters.
b) Prokaryotic cells have multiple rod-shaped chromosomes.
c) Prokaryotic cells are found in chains of rods but not single rods.
d) Prokaryotic cells have a nucleus surrounded by a complex nuclear membrane.
This is correct because prokaryotic cells can form cocus in both pairs and clusters
Which statement describes eukaryotic cells?
a) The exoskeletons of eukaryotic cells maintain and support the cells' shapes.
b) The nuclei of eukaryotic cells are surrounded by complex nuclear
membranes.
c) The genomes of eukaryotic cells are usually packaged in single circular
chromosomes.
d) The organelles of eukaryotic cells are held in place by semipermeable
exoskeletons.
Which statement describes eukaryotic flagella?
a) Eukaryotic flagella can cover the entire surface of a cell.
b) Eukaryotic flagella are rotating structures.
c) Eukaryotic flagella have twelve pairs of microtubules.
d) Eukaryotic flagella are flexible, whip-like structures.
Which statement describes the endomembrane system?
a) It is attached to the smooth endoplasmic reticulum and makes proteins for
insertion into the cell membrane.
b) It includes the Golgi apparatus, lysosomes, and vesicles.
,c) It is a system that uses diffusion to transport materials inside of the cell.
d) It lacks membrane-bound organelles.
Which statement accurately describes similarities between protozoa and fungi?
a) Both perform chemosynthesis.
b) Both can be harmful or harmless depending on the context.
c) Both are made of long filaments that form visible colonies.
d) Both move with help from cilia and flagella.
Why are algae considered photosynthetic organisms?
a) Algae cell walls are constructed with a material called peptidoglycan.
b) Algae contain substances that can be converted into biofuels.
c) Algae produce chemical energy from the sun's light energy.
d) Algae create waste products that other organisms can use to make energy.
Why are plasmids important to the survival of organisms?
a) Plasmids exclusively contain the genes responsible for cellular replication in
bacteria.
b) Plasmids can store excess nutrients in the cytoplasm of the cell.
c) Plasmids protect the bacterial genome in a dormant state during unfavorable
environmental conditions.
d) Plasmids carry genetic material, apart from the genome, that can benefit the
organism.
Plasmids often carry genes that can offer beneficial traits such as antibiotic
resistance
Which statement describes bacteria?
a) Some bacteria are eukaryotes.
b) Some bacteria have cell walls composed of mycolic acid.
c) Some bacteria are motile by cilia.
d) Some bacteria have cell walls composed of chitin.
Mycolic acid can be found in the cell walls of acid-fast bacteria
Why are prokaryotes vital to life?
,Prokaryotes are vital to life because they are able to recycle elements like carbon
and nutrients. Organisms like animals need organic carbon in order to grow but,
unlike prokaryotes, they are unable to use inorganic carbon sources like CO2. The
enzyme nitrogenase is only found in prokaryotes
Which aspect of nutrient cycling is performed only by prokaryotes?
a) Respiration process
b) Carbon fixation
c) Nitrate assimilation
d) Nitrogen fixation
The enzyme nitrogenase is only found in prokaryotes; it is vital to life and the
process of nitrogen fixation
How does microbial bioremediation benefit the environment?
a) By helping to minimize the growth of pathogens in different parts of the body
b) By helping to metabolize and remove pollutants in the atmosphere
c) By producing complex organic pharmaceutical compounds used in antibiotics,
vaccines, and vitamins
d) By producing gases, such as carbon dioxide, which are used to make biofuels
This is the correct answer because the definition of bioremediation is the process
of bacteria using a toxic structure to grow which leads to it being removed from
the environment. Occurs often by breaking it down into its nontoxic components
What describes the relationship of pathogens to virulence?
a) Highly virulent pathogens almost always lead to a disease state when
introduced to the body.
b) Pathogens that cause an infection cannot also be virulent.
c) Highly virulent pathogens are highly susceptible to the human immune
system.
d) Less virulent pathogens are less likely to lead to an infection.
, What is the key difference between a primary pathogen and an opportunistic
pathogen?
a) Primary pathogens can be fought off by the body's immune defense system,
whereas opportunistic pathogens require synthetic interventions.
b) Primary pathogens can infect certain people, whereas opportunistic
pathogens can infect anyone.
c) Primary pathogens can infect anyone, whereas opportunistic pathogens can
cause disease if the host is immunocompromised.
d) Primary pathogens are part of the human microbiome, whereas opportunistic
pathogens are transmitted from another host.
How can disease expression be described?
a) Pathogens with high virulence tend to cause symptoms that include low-
grade fevers or headaches.
b) The infectious dose that is needed to cause illness is consistent from person
to person.
c) Virulent microorganisms result in the same form of disease in the host
regardless of the route of transmission.
d) Signs and symptoms associated with illness can be a result of many things,
including an immune response
What is the correct understanding of the median infectious dose?
a) It is the number of pathogenic cells required to kill 50% of infected animals.
b) It is the number of pathogenic cells required to cause active infection in 50%
of inoculated animals.
c) It is the amount of toxin required to see an immune response to infection in
50% of people.
d) It is the amount of toxin required to infect 50% of the human population.
Which structure aids in the evasion of phagocytosis by preventing immune cells
from adhering to pathogens?
a) Pili
b) Fimbriae
c) Peptidoglycan
d) Capsule
QUESTIONS, DETAILED ANSWERS & RATIONALES | PASS
WITH CONFIDENCE
Which statement describes prokaryotic cells?
a) Prokaryotic cells are found in coccus form in both pairs and clusters.
b) Prokaryotic cells have multiple rod-shaped chromosomes.
c) Prokaryotic cells are found in chains of rods but not single rods.
d) Prokaryotic cells have a nucleus surrounded by a complex nuclear membrane.
This is correct because prokaryotic cells can form cocus in both pairs and clusters
Which statement describes eukaryotic cells?
a) The exoskeletons of eukaryotic cells maintain and support the cells' shapes.
b) The nuclei of eukaryotic cells are surrounded by complex nuclear
membranes.
c) The genomes of eukaryotic cells are usually packaged in single circular
chromosomes.
d) The organelles of eukaryotic cells are held in place by semipermeable
exoskeletons.
Which statement describes eukaryotic flagella?
a) Eukaryotic flagella can cover the entire surface of a cell.
b) Eukaryotic flagella are rotating structures.
c) Eukaryotic flagella have twelve pairs of microtubules.
d) Eukaryotic flagella are flexible, whip-like structures.
Which statement describes the endomembrane system?
a) It is attached to the smooth endoplasmic reticulum and makes proteins for
insertion into the cell membrane.
b) It includes the Golgi apparatus, lysosomes, and vesicles.
,c) It is a system that uses diffusion to transport materials inside of the cell.
d) It lacks membrane-bound organelles.
Which statement accurately describes similarities between protozoa and fungi?
a) Both perform chemosynthesis.
b) Both can be harmful or harmless depending on the context.
c) Both are made of long filaments that form visible colonies.
d) Both move with help from cilia and flagella.
Why are algae considered photosynthetic organisms?
a) Algae cell walls are constructed with a material called peptidoglycan.
b) Algae contain substances that can be converted into biofuels.
c) Algae produce chemical energy from the sun's light energy.
d) Algae create waste products that other organisms can use to make energy.
Why are plasmids important to the survival of organisms?
a) Plasmids exclusively contain the genes responsible for cellular replication in
bacteria.
b) Plasmids can store excess nutrients in the cytoplasm of the cell.
c) Plasmids protect the bacterial genome in a dormant state during unfavorable
environmental conditions.
d) Plasmids carry genetic material, apart from the genome, that can benefit the
organism.
Plasmids often carry genes that can offer beneficial traits such as antibiotic
resistance
Which statement describes bacteria?
a) Some bacteria are eukaryotes.
b) Some bacteria have cell walls composed of mycolic acid.
c) Some bacteria are motile by cilia.
d) Some bacteria have cell walls composed of chitin.
Mycolic acid can be found in the cell walls of acid-fast bacteria
Why are prokaryotes vital to life?
,Prokaryotes are vital to life because they are able to recycle elements like carbon
and nutrients. Organisms like animals need organic carbon in order to grow but,
unlike prokaryotes, they are unable to use inorganic carbon sources like CO2. The
enzyme nitrogenase is only found in prokaryotes
Which aspect of nutrient cycling is performed only by prokaryotes?
a) Respiration process
b) Carbon fixation
c) Nitrate assimilation
d) Nitrogen fixation
The enzyme nitrogenase is only found in prokaryotes; it is vital to life and the
process of nitrogen fixation
How does microbial bioremediation benefit the environment?
a) By helping to minimize the growth of pathogens in different parts of the body
b) By helping to metabolize and remove pollutants in the atmosphere
c) By producing complex organic pharmaceutical compounds used in antibiotics,
vaccines, and vitamins
d) By producing gases, such as carbon dioxide, which are used to make biofuels
This is the correct answer because the definition of bioremediation is the process
of bacteria using a toxic structure to grow which leads to it being removed from
the environment. Occurs often by breaking it down into its nontoxic components
What describes the relationship of pathogens to virulence?
a) Highly virulent pathogens almost always lead to a disease state when
introduced to the body.
b) Pathogens that cause an infection cannot also be virulent.
c) Highly virulent pathogens are highly susceptible to the human immune
system.
d) Less virulent pathogens are less likely to lead to an infection.
, What is the key difference between a primary pathogen and an opportunistic
pathogen?
a) Primary pathogens can be fought off by the body's immune defense system,
whereas opportunistic pathogens require synthetic interventions.
b) Primary pathogens can infect certain people, whereas opportunistic
pathogens can infect anyone.
c) Primary pathogens can infect anyone, whereas opportunistic pathogens can
cause disease if the host is immunocompromised.
d) Primary pathogens are part of the human microbiome, whereas opportunistic
pathogens are transmitted from another host.
How can disease expression be described?
a) Pathogens with high virulence tend to cause symptoms that include low-
grade fevers or headaches.
b) The infectious dose that is needed to cause illness is consistent from person
to person.
c) Virulent microorganisms result in the same form of disease in the host
regardless of the route of transmission.
d) Signs and symptoms associated with illness can be a result of many things,
including an immune response
What is the correct understanding of the median infectious dose?
a) It is the number of pathogenic cells required to kill 50% of infected animals.
b) It is the number of pathogenic cells required to cause active infection in 50%
of inoculated animals.
c) It is the amount of toxin required to see an immune response to infection in
50% of people.
d) It is the amount of toxin required to infect 50% of the human population.
Which structure aids in the evasion of phagocytosis by preventing immune cells
from adhering to pathogens?
a) Pili
b) Fimbriae
c) Peptidoglycan
d) Capsule
