exam study questions and answers 2025
The study of evolutionary relationships among organisms is called ______. - Correct
Ans-phylogeny
The three cell types discussed, eukaryotes, archaea, and bacteria, all derived from
______. - Correct Ans-Last Universal Common Ancestor
Organisms called parasites are ______. - Correct Ans-always harmful to their host
Which of the following does not indicate microbe involvement in energy and nutrient
flow? - Correct Ans-Thermal hot springs warmed by heat from earth's interior
The subatomic particles that surround the nucleus are the ______. - Correct Ans-
Electrons
The number one worldwide infectious diseases are ______. - Correct Ans-respiratory
disease
A fat is called _____ if all carbons of the fatty acid chain are single-bonded to 2 other
carbons and 2 hydrogens. - Correct Ans-saturated
One technique for staining bacteria for viewing under the microscope is called the Gram
stain. In this technique, alcohol is used as a decolorizer because it degrades the outer
membrane found in some bacteria. What chemical component of the cell does alcohol
affect? - Correct Ans-lipid
If a microbiologist is studying a specimen at a total magnification of 950X, what is the
magnifying power of the objective lens if the ocular lens is 10X? - Correct Ans-95X
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? - Correct Ans-cell size of 0.5 to 2 microns
Which type of microscope achieves the greatest resolution and highest magnification? -
Correct Ans-electron
Which of the following is produced by adding 1% to 5% agar to nutrient broth that is
then boiled and cooled? - Correct Ans-a solid medium
a spongiform encephalopathy of humans - Correct Ans-Creutzfeldt-Jacob disease
,The term that refers to flagella at both poles of the cell is ______. - Correct Ans-
amphitrichous
In the condition called athlete's foot, the fungus Trichophyton consumes the keratin
protein found in hair, nails, and dead skin. Which of the following descriptors does not
apply to Trichophyton? - Correct Ans-saprobe
During the Gram stain, the application of alcohol results in the decolorization of ______
cells. - Correct Ans-gram-negative
The size of a eukaryotic ribosome is ______ - Correct Ans-80s
Sterilizing filters have a pore size of 0.22 μm. Which of the following statements is true?
- Correct Ans-Bacterial cells are typically between 1-10 μm and are blocked by the filter,
whereas most viruses are between 20 and 200 nm and therefore pass through.
One of the principal viral capsid shapes is a 20-sided figure with 12 evenly spaced
corners referred to as a/an _____ capsid. - Correct Ans-icosahedral
Amoebic dysentery is most commonly contracted through - Correct Ans-fecal oral
the viral genome inserting into bacterial host chromosome - Correct Ans-lysogeny
Which of the following is not associated with every virus? - Correct Ans-envelope
When bacilli in a chain fold back upon each other like a hinge, this cellular arrangement
is termed a ______. - Correct Ans-palisade
proteins associated with DNA in the nucleus. - Correct Ans-histones
Viral tissue specificities are called ______. - Correct Ans-tropisms
the term that refers to the presence of a tuft of flagella emerging from a single site is
______. - Correct Ans-lophotrichous
E. coli bacteria normally live in the human gut and produce vitamin K that the body
uses. This is best termed a ______ relationship. - Correct Ans-mutualistic
Termites are insects that require the protozoan Trichonympha in their gut to synthesize
the enzyme cellulase to degrade the cellulose in wood. The protozoan uses the end
products of the cellulose breakdown (glucose). This is a(n) ______ relationship. -
Correct Ans-mutualistic
The phase of the bacterial growth curve in which newly inoculated cells are adjusting to
their new environment, metabolizing but not growing at an exponential rate, is the
______. - Correct Ans-lag phase
, The cell wall will help prevent the cell from bursting in ______ conditions. - Correct Ans-
hypotonic
This microbe is photosynthetic, but in the absence of light it can use organic compounds
as an energy source. Its carbon source is an organic compound. The appropriate
classification for this organism would be ______. - Correct Ans-photoheterotroph
A microorganism that has an optimum growth temperature of 37°C, but can survive
short exposure to high temperatures is called a(n) ______. - Correct Ans-thermoduric
microbe
the end product binding to enzyme in noncompetitive site - Correct Ans-Noncompetitive
inhibition
Ribozymes are ______. - Correct Ans-catalysts for RNA splicing
Most electron carriers are ______. - Correct Ans-coenzymes
what is the usual net production of ATP? - Correct Ans-2
Exergonic reactions occur during - Correct Ans-aerobic cellular respiration
Each nucleotide is composed of - Correct Ans-one phosphate, one nitrogenous base,
and one sugar
A frameshift is caused by ______ mutations. - Correct Ans-deletion and insertion
The fields of genomics and proteomics differ in that - Correct Ans-genomics refers to
the study of an organism's entire genome, whereas proteomics is the study of
expressed proteins
endosymbiotic theory - Correct Ans-eukaryotes
Replication of DNA begins at a/an _______ rich area. - Correct Ans-adenine-thymine
A/an _____ is the protein shell around the nucleic acid core of a virus. - Correct Ans-
capsid
The long, thread-like branching cells of molds are called ______. - Correct Ans-hyphae
in which stage of aerobic respiration is water produced? - Correct Ans-the electron
transport system
A bacteriophage transfers a random fragment of DNA of the previous host to the current
host. This is an example of - Correct Ans-generalized transduction