BIO 250 STRAIGHTERLINE MICROBIOLOGY
REAL PRACTICE 2026\2027 QUESTIONS
ANDCORRECT ANSWER s.
The purpose of staining cells on a microscope slide is to ______. Select
one:
a. kill them
b. secure them to the slide
c. enlarge the cells
d. add contrast to see them better
e. observe motility -CORRECT ANSWER -d. add contrast to see them better
A microbiologist must culture a patient's feces for intestinal pathogens. Which of
the following components would likely be present in a selective medium for this
purpose? Select one:
a. NaCl
b. Sheep red blood cells
c. Bile salts
d. Thioglycolic acid
e. Peptone -CORRECT ANSWER -c. Bile salts Organisms called parasites are
______.
Select one:
a. always harmful to their host
b. the decomposers in ecosystems
c. always viruses
d. free-living -CORRECT ANSWER -always harmful to their host
Trees of life that illustrate the phylogenetic relationships of all organisms were
traditionally based on ______; newer methods for determining phylogeny rely on
______.
Select one:
a. morphology; nucleic acid sequences
b. nucleic acid sequences; morphology
,c. morphology; virology
d. morphology; nutritional requirements
e. nucleic acid sequences; microbiomes -CORRECT ANSWER -a. morphology;
nucleic acid sequences
What is the maximum number of electrons in the first energy shell of an atom?
Select one: a. 2
b. 4
c. 8
d. 18
e. 32 -CORRECT ANSWER -a. 2
Which of the following is not true about enzymes?
Select one:
a. Enzymes are found in all cells.
b. Enzymes are catalysts.
c. Enzymes participate in the cell's chemical reactions.
d. Enzymes can be denaturated by heat and other agents.
e. Enzymes have high-energy bonds between phosphates -CORRECT ANSWER
Enzymes have high-energy bonds between phosphates
NASA has published a list of criteria for identifying fossil bacteria in samples from
Mars, as part of a search for evidence of life. Which of the following is good
evidence for the presence of bacterial cells?
Select one:
a. Cell size of 0.5 to 2 microns
b. Three-dimensional organization of cells in a starburst pattern
c. Absence of carbon in the material
d. No evidence of water in the surrounding mineral -CORRECT ANSWER -a. Cell
size of 0.5 to 2 microns
Which type of medium would be the best choice when shipping a sample of
bacteria from a clinic to a laboratory for testing?
Select one:
,a. Transport medium
b. Eosin-methylene blue agar
c. Blood agar
d. Thioglycolate medium -CORRECT ANSWER -a. Transport medium
The orderly arrangement of organisms into a hierarchy of taxa is called ______.
Select one:
a. classification
b. identification
c. nomenclature
d. experimentation
e. biotechnology -CORRECT ANSWER -a. classification
A microbiologist inoculates Staphylococcus aureus into a culture medium.
Following incubation, both Staphylococcus aureus and Staphylococcus epidermidis
are determined to be growing in this culture. What is the most likely explanation?
Select one:
a. The microbiologist used too much inoculum.
b. The culture was contaminated.
c. The incubation temperature was incorrect.
d. The culture medium was selective.
e. The culture medium was differential. -CORRECT ANSWER -b. The culture
was contaminated.
Disease-causing microorganisms are called ______.
Select one:
a. decomposers
b. bacteria
c. pathogens
d. eukaryotes
e. fermenters -CORRECT ANSWER -c. pathogens
, Which scientific field is involved in the identification, classification, and naming of
organisms?
Select one:
a. Nomenclature
b. Taxonomy
c. Phylogeny
d. Pathology
e. Epidemiology -CORRECT ANSWER -b. Taxonomy
Covalent bonds Select
one:
a. result from losing electrons.
b. are always polar.
c. are always nonpolar.
d. result from sharing electrons.
e. result from gaining electrons. -CORRECT ANSWER -
Using microbes to detoxify a site contaminated with heavy metals is an example of
______. Select one:
a. biotechnology
b. bioremediation
c. decomposition
d. immunology
e. epidemiology -CORRECT ANSWER -bioremediation
Which of the following statements is incorrect regarding protein structure? Select
one:
a. The interaction between various R groups of amino acids determines the
primary structure of a protein.
b. Beta-pleated sheets are a type of protein secondary structure.
c. The folding of a protein to form its active site creates its tertiary structure.
REAL PRACTICE 2026\2027 QUESTIONS
ANDCORRECT ANSWER s.
The purpose of staining cells on a microscope slide is to ______. Select
one:
a. kill them
b. secure them to the slide
c. enlarge the cells
d. add contrast to see them better
e. observe motility -CORRECT ANSWER -d. add contrast to see them better
A microbiologist must culture a patient's feces for intestinal pathogens. Which of
the following components would likely be present in a selective medium for this
purpose? Select one:
a. NaCl
b. Sheep red blood cells
c. Bile salts
d. Thioglycolic acid
e. Peptone -CORRECT ANSWER -c. Bile salts Organisms called parasites are
______.
Select one:
a. always harmful to their host
b. the decomposers in ecosystems
c. always viruses
d. free-living -CORRECT ANSWER -always harmful to their host
Trees of life that illustrate the phylogenetic relationships of all organisms were
traditionally based on ______; newer methods for determining phylogeny rely on
______.
Select one:
a. morphology; nucleic acid sequences
b. nucleic acid sequences; morphology
,c. morphology; virology
d. morphology; nutritional requirements
e. nucleic acid sequences; microbiomes -CORRECT ANSWER -a. morphology;
nucleic acid sequences
What is the maximum number of electrons in the first energy shell of an atom?
Select one: a. 2
b. 4
c. 8
d. 18
e. 32 -CORRECT ANSWER -a. 2
Which of the following is not true about enzymes?
Select one:
a. Enzymes are found in all cells.
b. Enzymes are catalysts.
c. Enzymes participate in the cell's chemical reactions.
d. Enzymes can be denaturated by heat and other agents.
e. Enzymes have high-energy bonds between phosphates -CORRECT ANSWER
Enzymes have high-energy bonds between phosphates
NASA has published a list of criteria for identifying fossil bacteria in samples from
Mars, as part of a search for evidence of life. Which of the following is good
evidence for the presence of bacterial cells?
Select one:
a. Cell size of 0.5 to 2 microns
b. Three-dimensional organization of cells in a starburst pattern
c. Absence of carbon in the material
d. No evidence of water in the surrounding mineral -CORRECT ANSWER -a. Cell
size of 0.5 to 2 microns
Which type of medium would be the best choice when shipping a sample of
bacteria from a clinic to a laboratory for testing?
Select one:
,a. Transport medium
b. Eosin-methylene blue agar
c. Blood agar
d. Thioglycolate medium -CORRECT ANSWER -a. Transport medium
The orderly arrangement of organisms into a hierarchy of taxa is called ______.
Select one:
a. classification
b. identification
c. nomenclature
d. experimentation
e. biotechnology -CORRECT ANSWER -a. classification
A microbiologist inoculates Staphylococcus aureus into a culture medium.
Following incubation, both Staphylococcus aureus and Staphylococcus epidermidis
are determined to be growing in this culture. What is the most likely explanation?
Select one:
a. The microbiologist used too much inoculum.
b. The culture was contaminated.
c. The incubation temperature was incorrect.
d. The culture medium was selective.
e. The culture medium was differential. -CORRECT ANSWER -b. The culture
was contaminated.
Disease-causing microorganisms are called ______.
Select one:
a. decomposers
b. bacteria
c. pathogens
d. eukaryotes
e. fermenters -CORRECT ANSWER -c. pathogens
, Which scientific field is involved in the identification, classification, and naming of
organisms?
Select one:
a. Nomenclature
b. Taxonomy
c. Phylogeny
d. Pathology
e. Epidemiology -CORRECT ANSWER -b. Taxonomy
Covalent bonds Select
one:
a. result from losing electrons.
b. are always polar.
c. are always nonpolar.
d. result from sharing electrons.
e. result from gaining electrons. -CORRECT ANSWER -
Using microbes to detoxify a site contaminated with heavy metals is an example of
______. Select one:
a. biotechnology
b. bioremediation
c. decomposition
d. immunology
e. epidemiology -CORRECT ANSWER -bioremediation
Which of the following statements is incorrect regarding protein structure? Select
one:
a. The interaction between various R groups of amino acids determines the
primary structure of a protein.
b. Beta-pleated sheets are a type of protein secondary structure.
c. The folding of a protein to form its active site creates its tertiary structure.
