Science / Biology / Microbiology
Straighterline Microbiology EXAM 2025 | ALL
QUESTIONS AND CORRECT ANSWERS | GRADED
A+ | VERIFIED ANSWERS | LATEST EXAM (JUST
RELEASED)
QUESTIONS ANSWERS
Which Islamic physician laid the foundation b.Ibn Sina
for historical and contemporary quarantine
methods and described mechanisms of
contagion?
Select one:
a.Thucydides
b.Ibn Sina
c.Hippocrates
d.Abū Bakr al-Rāzī
Which technique did Carl Woese and George c.Genetic sequencing
Fox use to analyze the
evolutionary relationships among
organisms?
Select one:
a.X-ray crystallography
b.Microscopy c.Genetic
sequencing
d.Electrophoresis
Page 1
,Which of the following statements about Robert a.
Koch's achievements in Robert Koch was the first to demonstrate the connection between a single, isolated
microbiology is correct? microbe and a known human disease.
Select one:
a. Robert Koch was the first to demonstrate
the connection between a single, isolated
microbe and a known human disease.
b. Robert Koch demonstrated that
fermentation is caused by chemical
reactions, not microorganisms.
c. Robert Koch invented the process of
pasteurization to kill harmful
microorganisms in food and drink items.
d.Robert Koch discovered the structure of
DNA.
What distinguishes the five-kingdom a.It included fungi as a separate kingdom.
classification system proposed by Robert
Whittaker?
Select one:
a. It included fungi as a separate kingdom.
b. It was based solely on observable
characteristics.
c. It classified all organisms into either
plants or animals.
d. It introduced the concept of domains
above the kingdom level.
Imagine you're a biologist conducting field b.The genus name is abbreviated using its first initial followed by a period, followed by the
research in a remote jungle, where you full species name.
stumble upon a new species of frog. After
identifying and naming the frog species,
you need to refer to it multiple times in
your research notes. How would you
typically abbreviate the organism's genus and
species names after their initial mention as
perthe rules of binomial
nomenclature?
Select one:
a.Both the genus and species names are
abbreviated using their first three letters.
b.The genus name is abbreviated using its first
initial followed by a period, followed by the
full species name.
c.Neither the genus nor the species names are
abbreviated in subsequent mentions. d.Only
the species name is abbreviated,
using its first letter followed by a period and
the full genus name.
What is the most common sterol found in animal a.Cholesterol
tissues?
Select one:
a.Cholesterol
b.Ergosterol
c.Beta-carotene
d.Hopanoids
Page 2
,What is the term used for the unique d.Nodule
structure formed by leguminous plants in
symbiosis with rhizobia?
Select one:
a.Lichen
b.Tuber
c.Mycorrhizae
d.Nodule
Which disaccharide is composed of glucose b.Sucrose
and fructose units?
Select one:
a.Maltose
b.Sucrose
c.Galactose
d.Lactose
What is the primary structure of a protein c.Amino acid residues forming a peptide chain
composed of?
Select one:
a. Disulfide bonds between amino acids
b. Hydrogen bonds between amino acids
c. Amino acid residues forming a peptide
chain
d. Polar interactions between amino acid
side chains
Match the following saccharides with their c.A-2, B-3, C-4, D-1
descriptions or properties:
SaccharideDescriptionA. Glucose1. Primary
energy storage molecule in animals and
bacteria.B. Sucrose2. Most abundant
monosaccharide in nature.C. Cellulose3.
Table sugar, is made up of glucose and a
fructose molecule.D. Glycogen4. Structural
component of plant cell walls.
Select one:
a.A-1, B-3, C-2, D-4
b.A-4, B-2, C-3, D-1
c.A-2, B-3, C-4, D-1
d.A-3, B-4, C-1, D-2
Which of the following bacterial groups b.Atypical bacteria
cannot be stained by the standard Gram stain
procedure?
Select one:
a. Proteobacteria
b. Atypical bacteria
c. CFB bacteria
d.Spirochetes
Page 3
, Which component of the gram-negative b.Lipopolysaccharides
bacterial cell envelope functions as an
endotoxin and contributes to symptoms such
as fever and septic shock?
Select one:
a. O antigens
b. Lipopolysaccharides
c. Murein lipoproteins
d. Lipid A
What structures protect the bacterial d.Endospores
genome in a dormant state when
environmental conditions are unfavorable?
Select one:
a. Pili
b. Capsules
c.Flagella
d.Endospores
Which of the following statements a.They represent an early evolutionary form of bacteria.
accurately describes the deeply branching
bacteria?
Select one:
a. They represent an early evolutionary form of
bacteria.
b. They thrive in aerobic conditions.
c. They are typically found in cold
environments.
d. They are commonly associated with
human gut microbiota.
Which of the following statements about the b.The plasma membrane, also known as the cell membrane or cytoplasmic
cell envelope and membranes in membrane, is present in both prokaryotic and eukaryotic cells and is selectively
prokaryotic and eukaryotic cells is correct? permeable.
Select one:
a. Only prokaryotic cells have a cell wall,
while eukaryotic cells do not.
b. The plasma membrane, also known as the cell
membrane or cytoplasmic membrane, is
present in both prokaryotic and
eukaryotic cells and is selectively
permeable.
c. The cell envelope in prokaryotic cells
always includes a nuclear envelope.
d. In eukaryotic cells, the plasma membrane is
not selectively permeable.
Page 4
Straighterline Microbiology EXAM 2025 | ALL
QUESTIONS AND CORRECT ANSWERS | GRADED
A+ | VERIFIED ANSWERS | LATEST EXAM (JUST
RELEASED)
QUESTIONS ANSWERS
Which Islamic physician laid the foundation b.Ibn Sina
for historical and contemporary quarantine
methods and described mechanisms of
contagion?
Select one:
a.Thucydides
b.Ibn Sina
c.Hippocrates
d.Abū Bakr al-Rāzī
Which technique did Carl Woese and George c.Genetic sequencing
Fox use to analyze the
evolutionary relationships among
organisms?
Select one:
a.X-ray crystallography
b.Microscopy c.Genetic
sequencing
d.Electrophoresis
Page 1
,Which of the following statements about Robert a.
Koch's achievements in Robert Koch was the first to demonstrate the connection between a single, isolated
microbiology is correct? microbe and a known human disease.
Select one:
a. Robert Koch was the first to demonstrate
the connection between a single, isolated
microbe and a known human disease.
b. Robert Koch demonstrated that
fermentation is caused by chemical
reactions, not microorganisms.
c. Robert Koch invented the process of
pasteurization to kill harmful
microorganisms in food and drink items.
d.Robert Koch discovered the structure of
DNA.
What distinguishes the five-kingdom a.It included fungi as a separate kingdom.
classification system proposed by Robert
Whittaker?
Select one:
a. It included fungi as a separate kingdom.
b. It was based solely on observable
characteristics.
c. It classified all organisms into either
plants or animals.
d. It introduced the concept of domains
above the kingdom level.
Imagine you're a biologist conducting field b.The genus name is abbreviated using its first initial followed by a period, followed by the
research in a remote jungle, where you full species name.
stumble upon a new species of frog. After
identifying and naming the frog species,
you need to refer to it multiple times in
your research notes. How would you
typically abbreviate the organism's genus and
species names after their initial mention as
perthe rules of binomial
nomenclature?
Select one:
a.Both the genus and species names are
abbreviated using their first three letters.
b.The genus name is abbreviated using its first
initial followed by a period, followed by the
full species name.
c.Neither the genus nor the species names are
abbreviated in subsequent mentions. d.Only
the species name is abbreviated,
using its first letter followed by a period and
the full genus name.
What is the most common sterol found in animal a.Cholesterol
tissues?
Select one:
a.Cholesterol
b.Ergosterol
c.Beta-carotene
d.Hopanoids
Page 2
,What is the term used for the unique d.Nodule
structure formed by leguminous plants in
symbiosis with rhizobia?
Select one:
a.Lichen
b.Tuber
c.Mycorrhizae
d.Nodule
Which disaccharide is composed of glucose b.Sucrose
and fructose units?
Select one:
a.Maltose
b.Sucrose
c.Galactose
d.Lactose
What is the primary structure of a protein c.Amino acid residues forming a peptide chain
composed of?
Select one:
a. Disulfide bonds between amino acids
b. Hydrogen bonds between amino acids
c. Amino acid residues forming a peptide
chain
d. Polar interactions between amino acid
side chains
Match the following saccharides with their c.A-2, B-3, C-4, D-1
descriptions or properties:
SaccharideDescriptionA. Glucose1. Primary
energy storage molecule in animals and
bacteria.B. Sucrose2. Most abundant
monosaccharide in nature.C. Cellulose3.
Table sugar, is made up of glucose and a
fructose molecule.D. Glycogen4. Structural
component of plant cell walls.
Select one:
a.A-1, B-3, C-2, D-4
b.A-4, B-2, C-3, D-1
c.A-2, B-3, C-4, D-1
d.A-3, B-4, C-1, D-2
Which of the following bacterial groups b.Atypical bacteria
cannot be stained by the standard Gram stain
procedure?
Select one:
a. Proteobacteria
b. Atypical bacteria
c. CFB bacteria
d.Spirochetes
Page 3
, Which component of the gram-negative b.Lipopolysaccharides
bacterial cell envelope functions as an
endotoxin and contributes to symptoms such
as fever and septic shock?
Select one:
a. O antigens
b. Lipopolysaccharides
c. Murein lipoproteins
d. Lipid A
What structures protect the bacterial d.Endospores
genome in a dormant state when
environmental conditions are unfavorable?
Select one:
a. Pili
b. Capsules
c.Flagella
d.Endospores
Which of the following statements a.They represent an early evolutionary form of bacteria.
accurately describes the deeply branching
bacteria?
Select one:
a. They represent an early evolutionary form of
bacteria.
b. They thrive in aerobic conditions.
c. They are typically found in cold
environments.
d. They are commonly associated with
human gut microbiota.
Which of the following statements about the b.The plasma membrane, also known as the cell membrane or cytoplasmic
cell envelope and membranes in membrane, is present in both prokaryotic and eukaryotic cells and is selectively
prokaryotic and eukaryotic cells is correct? permeable.
Select one:
a. Only prokaryotic cells have a cell wall,
while eukaryotic cells do not.
b. The plasma membrane, also known as the cell
membrane or cytoplasmic membrane, is
present in both prokaryotic and
eukaryotic cells and is selectively
permeable.
c. The cell envelope in prokaryotic cells
always includes a nuclear envelope.
d. In eukaryotic cells, the plasma membrane is
not selectively permeable.
Page 4
