Microbiology ID Exam 3 Final Exam Prep
Exam 2025 Test Questions And Correct
Verified Answers
Which of the following genetics elements must be
present in ALL bacteria (not an optional genetic
components)?
chromosome
What is the most critical aspect of a bacteriophage to
enable it to participate in generalized transduction?
it packages DNA into the capsid in a sloppy manner
Cells that are naturally competent can
,Take up naked DNA from the environment
Conjugation plasmids encode a _____________ to
transfer a plasmid between different bacteria.
Pilus
What horizontal gene transfer mechanisms can move
transposons between strains?
Transformation, Transduction and Conjugation
Why are there several antibiotics that target the
bacterial ribosome without harming the human host?
Because the bacterial ribosome is smaller and
different enough from human ribosomes
Which antibiotic inhibits bacterial transcription?
Rifampin
Which of the following antibiotics does NOT directly
affect protein synthesis?
Nalidixic acid
Which of the following does not accurately describe
bacterial biofilms?
Bacterial replication is faster than for planktonic cells
,Which of the following accurately describe bacterial
biofilms?
the bacteria are so crowded in a biofilm, their access
to nutrients is very limited, especially those in the
middle, so they grow more slowly.
What is true about type 3 secretion in gram-negative
bacteria?
It injects proteins into host cells; Types 4 and 6 also
do this
Rifampin inhibits
RNA polymerase subunit beta, which is encoded by
the rpoB gene. BTW, resistance to rif usually comes
from a point mutation in rpoB
Nalidixic acid inhibits
DNA synthesis via DNA gyrase. All of the other inhibit
protein synthesis at the ribosome.
Which of the following does NOT accurately describe
structural relationships of bacteria?
wall-less: LPS and cholesterol
, Why are gram-negative bacteria resistant to
bacitracin and vancomycin?
porin size; they are are too big to get through the
porins of the outer membrane.
Which part of lipopolysaccharide has the toxic
inflammatory activity?
lipid A
Which type of bacteria make spores?
Gram-positive rods
Which function is NOT carried out at the bacterial cell
membrane?
Endocytosis; Bacteria do not perform endocytosis
anywhere
Which function is carried out at the bacterial cell
membrane?
transport, motility, energy production, and
chromosomal segregation
Which of the following best describes the concept of
selective toxicity of antibiotics?
Exam 2025 Test Questions And Correct
Verified Answers
Which of the following genetics elements must be
present in ALL bacteria (not an optional genetic
components)?
chromosome
What is the most critical aspect of a bacteriophage to
enable it to participate in generalized transduction?
it packages DNA into the capsid in a sloppy manner
Cells that are naturally competent can
,Take up naked DNA from the environment
Conjugation plasmids encode a _____________ to
transfer a plasmid between different bacteria.
Pilus
What horizontal gene transfer mechanisms can move
transposons between strains?
Transformation, Transduction and Conjugation
Why are there several antibiotics that target the
bacterial ribosome without harming the human host?
Because the bacterial ribosome is smaller and
different enough from human ribosomes
Which antibiotic inhibits bacterial transcription?
Rifampin
Which of the following antibiotics does NOT directly
affect protein synthesis?
Nalidixic acid
Which of the following does not accurately describe
bacterial biofilms?
Bacterial replication is faster than for planktonic cells
,Which of the following accurately describe bacterial
biofilms?
the bacteria are so crowded in a biofilm, their access
to nutrients is very limited, especially those in the
middle, so they grow more slowly.
What is true about type 3 secretion in gram-negative
bacteria?
It injects proteins into host cells; Types 4 and 6 also
do this
Rifampin inhibits
RNA polymerase subunit beta, which is encoded by
the rpoB gene. BTW, resistance to rif usually comes
from a point mutation in rpoB
Nalidixic acid inhibits
DNA synthesis via DNA gyrase. All of the other inhibit
protein synthesis at the ribosome.
Which of the following does NOT accurately describe
structural relationships of bacteria?
wall-less: LPS and cholesterol
, Why are gram-negative bacteria resistant to
bacitracin and vancomycin?
porin size; they are are too big to get through the
porins of the outer membrane.
Which part of lipopolysaccharide has the toxic
inflammatory activity?
lipid A
Which type of bacteria make spores?
Gram-positive rods
Which function is NOT carried out at the bacterial cell
membrane?
Endocytosis; Bacteria do not perform endocytosis
anywhere
Which function is carried out at the bacterial cell
membrane?
transport, motility, energy production, and
chromosomal segregation
Which of the following best describes the concept of
selective toxicity of antibiotics?
