Microbiology Chapter 3 and 4(Openstax)
Test Questions with Complete
Rationales 2026/2027.
Which of the following is not considered evidence that supports the endosymbiotic theory? -
Answer Mitochondria and chloroplast chromosomes are structurally similar to bacterial
chromosomes.
Bacteria - Answer Prokaryotic
mushroom - Answer eukaryotic
elephant (Eukaryotes) - Answer Prokaryotic
fly - Answer eukaryotic
nematode - Answer eukaryotic
fungi - Answer eukaryotic
archaea - Answer Prokaryotic
What term refers to a sticky bacteria exterior layer made of sugar? - Answer glycocalyx
What cell wall component is responsible for the extreme toxicity of gram-negative cells? -
Answer lipopolysaccharide (LPS)
What cellular structure is commonly found outside of the plasma membrane and assists in
protection against osmotic pressure changes? - Answer cell wall
In the image, the black circles represent solute that is dissolved in water. What direction will the
water move?
5% solute concentration on the outside of the circle, 45% solute concentration on the inside of
the circle - Answer Water will move into the cell.
, Consider that the cell wall of a certain bacteria is weak or damaged. If this cell were to burst due
to water moving into the cell, what type of solution must it be in? - Answer a hypotonic
solution
Suppose that you are observe a Gram stain of rod-shaped microorganisms that are linked in a
chain and stain pink. Which of the following phrases correctly describes the bacteria? - Answer
gram-negative staphylococcus
Suppose that you are observe a Gram stain of spherically-shaped microorganisms that are
clustered together and stain purple. Which of the following phrases correctly describes the
bacteria? - Answer gram-positive streptococcus
Ribosomes are found in all cells, both prokaryotic and eukaryotic. What statement correctly
describes their structure and function? - Answer Ribosomes are made of protein, and they
also make proteins.
In order to store excessive nutrients, prokaryotic cells often accumulate and store this excess in -
Answer inclusion bodies.
Suppose that a substance is being moved across a membrane from a region of higher
concentration to a region of lower concentration. If no energy is being used and there is no
participation by membrane carriers or channels, what type of transport is this? - Answer
simple diffusion
There are certain cellular components that are found in all cells, regardless of the organism. This
includes all of the follow except - Answer the nucleus
If a cell must expend energy to move substances from a region of low concentration to a region
of high concentration, this energy is most typically provided in the form of - Answer adenosine
triphosphate.
Match the organism with the material that typically composes its cell wall: archaea - Answer
pseudopeptidoglycan
Match the organism with the material that typically composes its cell wall: plants - Answer
cellulose
Match the organism with the material that typically composes its cell wall: fungi - Answer
Chitin
Test Questions with Complete
Rationales 2026/2027.
Which of the following is not considered evidence that supports the endosymbiotic theory? -
Answer Mitochondria and chloroplast chromosomes are structurally similar to bacterial
chromosomes.
Bacteria - Answer Prokaryotic
mushroom - Answer eukaryotic
elephant (Eukaryotes) - Answer Prokaryotic
fly - Answer eukaryotic
nematode - Answer eukaryotic
fungi - Answer eukaryotic
archaea - Answer Prokaryotic
What term refers to a sticky bacteria exterior layer made of sugar? - Answer glycocalyx
What cell wall component is responsible for the extreme toxicity of gram-negative cells? -
Answer lipopolysaccharide (LPS)
What cellular structure is commonly found outside of the plasma membrane and assists in
protection against osmotic pressure changes? - Answer cell wall
In the image, the black circles represent solute that is dissolved in water. What direction will the
water move?
5% solute concentration on the outside of the circle, 45% solute concentration on the inside of
the circle - Answer Water will move into the cell.
, Consider that the cell wall of a certain bacteria is weak or damaged. If this cell were to burst due
to water moving into the cell, what type of solution must it be in? - Answer a hypotonic
solution
Suppose that you are observe a Gram stain of rod-shaped microorganisms that are linked in a
chain and stain pink. Which of the following phrases correctly describes the bacteria? - Answer
gram-negative staphylococcus
Suppose that you are observe a Gram stain of spherically-shaped microorganisms that are
clustered together and stain purple. Which of the following phrases correctly describes the
bacteria? - Answer gram-positive streptococcus
Ribosomes are found in all cells, both prokaryotic and eukaryotic. What statement correctly
describes their structure and function? - Answer Ribosomes are made of protein, and they
also make proteins.
In order to store excessive nutrients, prokaryotic cells often accumulate and store this excess in -
Answer inclusion bodies.
Suppose that a substance is being moved across a membrane from a region of higher
concentration to a region of lower concentration. If no energy is being used and there is no
participation by membrane carriers or channels, what type of transport is this? - Answer
simple diffusion
There are certain cellular components that are found in all cells, regardless of the organism. This
includes all of the follow except - Answer the nucleus
If a cell must expend energy to move substances from a region of low concentration to a region
of high concentration, this energy is most typically provided in the form of - Answer adenosine
triphosphate.
Match the organism with the material that typically composes its cell wall: archaea - Answer
pseudopeptidoglycan
Match the organism with the material that typically composes its cell wall: plants - Answer
cellulose
Match the organism with the material that typically composes its cell wall: fungi - Answer
Chitin
