Molecular sequencing suggests that mitochondria arose from a group of prokaryotic
organisms within the
A) Crenarchaeota.
B) cyanobacteria.
C) iron-oxidizing bacteria.
D) Proteobacteria.
You are given an electron micrograph of a bacterial cell. In the micrograph you can
clearly see three thin layers of different densities surrounding the cell. Based on the
micrograph, you can infer that this cell is ________ and would appear ________ after
application of the Gram stain procedure.
A) gram-positive / purple
B) gram-negative / pink
C) gram-positive / pink
D) gram-negative / purple
Many West Nile virus infections are not properly identified because
A) the disease mimics malaria.
B) the symptoms are often subacute.
C) the disease is frequently fatal.
D) most physicians and diagnosticians are not aware of this disease.
The use of ________ to treat drinking water, which began in 1913, reduces the
incidence of waterborne diseases.
A) coagulation
B) chlorination
C) filtration
D) UV irradiation
Which of the following is a category of exotoxin?
A) cytolytic toxin
B) lipophilic toxin
C) α-toxin
D) β-toxin
Which of the following is/are NOT a degradation product of organic material?
A) carbon dioxide
B) methane
C) oxygen
D) carbon dioxide, methane, and oxygen
The collective term for the organisms living on or in the human body is
A) normal microbial flora.
B) fomite flora.
C) transient microbial flora.
D) pathogenic flora.
The 13C/12C isotopic ratio of geological rocks of different ages has been used as
evidence for or against past biological activity, because compounds of biological origin
A) do NOT contain 13C.
B) have a higher proportion of 13C that compounds of geological origin.
C) have a lower proportion of 13C that compounds of geological origin.
D) are not well preserved in geological samples.
Gene therapy viruses are usually constructed from which type of virus?
A) adenoviruses
B) cytomegaloviruses
C) polyomaviruses
D) poxviruses
How are T7 genes transcribed?
A) Host RNA polymerase is modified to recognize the T7 promoter.
B) Host RNA polymerase directly translates the T7 genes.
C) T7 has its own RNA polymerase, which is packaged in its capsid and injected into
the host during infection to transcribe T7 genes.
D) T7 has its own RNA polymerase, which must first be synthesized by the host.
Which of the following is a sulfide?
A) H2S
B) HS-
C) S2-
D) H2S, HS-, and S2- are all sulfides.
In B cell selection and tolerance, if no signal is generated from ________ cells, the B
cells remain unresponsive.
A) TC
B) TH
C) B7
D) CD28
Compounds such as pyruvate, acetyl-CoA, fructose-6-phosphate, oxaloacetate, and
other small organic compounds could be part of a(n)
A) metagenome.
B) metabolome.
C) interactome.
D) transcriptome.
The HPV vaccine has been recommended for
A) females 11-26.
B) females 26-45.
C) males.
D) males and females 11-26.
Plasma cells usually live for about one
A) week.
B) month.
C) year.
D) decade.
Which of the following is NOT a unifying characteristic of diplomonads and
parabasalids?
A) having flagella
B) lacking chloroplasts
C) lacking mitochondria
D) being multicellular
A drug that specifically inhibited the replication of the large DNA mass present in large
mitochondria would be MOST effective at killing
A) euglenids.
B) ciliates.
C) Trypanosoma spp.
D) Toxoplasma spp.
To discover a catabolic gene cluster, cloning large sequences of approximately 40 kbp
requires the utility of
A) bacterial artificial chromosomes (BACs).
B) cosmids or fosmids.
C) a eukaryotic host to house the large foreign DNA.
D) multiple gene fusions.
What adaptation do organisms have that tolerate high pressures?
A) decreased cell size
B) decreased lipid content
C) increased ribosome size
D) increased unsaturated fatty acids
Which of the following diseases is/are associated with organ-specific autoimmune
disease?
A) autoimmune hypothyroidism
B) juvenile (type I) diabetes
C) systemic lupus erythematosus (SLE)
D) autoimmune hypothyroidism and juvenile (type I) diabetes
The oxygen-free gas commonly employed during anoxic incubation of a bacterial
culture is a mixture of
A) nitrogen and carbon dioxide.
B) nitrogen and carbon monoxide.
C) nitrogen and argon.
D) nitrogen and hydrogen.
You are attempting to mutate lambda to affect whether lysis or lysogeny occurs after
lambda infection. Which mutation would INCREASE the chances of LYSOGENY over
lysis?
A) deletion or inactivation of the cI gene
B) deletion or inactivation of the cro gene
C) overexpression of the cro gene
D) deletion of both the cro and cI genes
The growth of viruses in a culture is described as a one-step growth curve, because
A) virion numbers show no increase during intracellular replication and can only be
counted after the virions burst from the host cell.
B) there is only one step in the viral life cycle which leads to only one replicative cycle
in a culture.
C) assembly and release actually occur in one step.
D) the eclipse phase prevents the plating and enumeration of virions although new
virions are produced at a steady rate during the eclipse phase.
In viruses, genetic information flows from ________ to ________.
A) RNA / virion
B) nucleic acid / protein
C) capsid / virion
D) DNA / protein
Anoxygenic phototrophs
A) may use a variety of electron donors for photosynthesis.
B) are an ancient monophyletic group of bacteria.
C) can be either autotrophic or heterotrophic.
D) can be either autotrophic or heterotrophic and may use a variety of electron donors
for photosynthesis.
Which of the following would NOT be a trait of a resistance plasmid?
A) It may carry antibiotic resistance genes.
B) It may carry heavy metal resistance genes.
C) It increases the host’s growth rate.
D) It may undergo genetic recombination.
Following antibiotic therapy, patients are often administered ________ to facilitate
recolonizaton of normal flora.
A) fluoride
B) iron
C) probiotics
D) antivirals
The CRISPR system
A) facilitates homologous recombination through a complex system of proteins and
clustered repeats.
B) recognizes foreign DNA sequences that have previously entered the cell and directs
the Cas proteins to destroy them.
C) repairs DNA and increases DNA damage tolerance during times of stress.
D) synthesizes gene transfer agents during stationary phase.
Which statement is TRUE regarding fungal spores?
A) Conidia are asexual spores.
B) Ascospores are sexual spores.
C) Basidiospores are sexual spores.
D) Conidia are asexual spores, and both ascospores and basidiospores are sexual spores.
During electron transport reactions,
A) OH– accumulates on the outside of the membrane while H+ accumulates on the
inside.
B) OH– accumulates on the inside of the membrane while H+ accumulates on the
outside.
C) both OH– and H+ accumulate on the inside of the membrane.
D) both OH– and H+ accumulate on the outside of the membrane.
In complementary base pairing of DNA, adenine pairs with ________ (or ________ in
RNA) and cytosine always pairs with ________.
A) guanine / uracil / thymine
B) uracil / thymine / guanine
C) thymine / guanine / uracil
D) thymine / uracil / guanine
Many pharmaceutical drugs specifically inhibit transcription in Bacteria but not
Archaea or Eukarya. Why would drugs that inhibit transcription only affect Bacteria
and not Archaea even though they are both prokaryotes?
A) Archaea and Eukarya have very similar ribosomes that are different than bacterial
ribosomes.
B) Bacteria lack a nucleus.
C) Archaea lack operons.
D) Archaea and Eukarya have very similar RNA polymerases that are different than
bacterial RNA polymerases.
Which statement BEST describes the habitats of the fungi?
A) Most fungi are aquatic, microscopic, and primarily freshwater.
B) Most fungi are aquatic and primarily marine.
C) Most fungi are terrestrial, microscopic, and inhabit soil or dead plant matter.
D) Most fungi are terrestrial and macroscopic.
Which is NOT a characteristic of a “primitive” state of microbial evolution?
A) hyperthermophilic
B) aerobic metabolism
C) small genome
D) branching near the root of the evolutionary tree of life
A ________ is a disease that primarily infects animals but can be transmitted to
humans.
A) nosocomial infection
B) zoonosis
C) vector infection
D) mudurane