GENETICS OF VIRUSES & BACTERIAL REVIEW QUESTIONS (Chapters 33, 34, 18)

Sample Answers

1. A virus injects its DNA into a cell. Some genes are transcribed quite rapidly. Those
    genes are probably involved in
    A. producing DNA polymerases
    B. producing viral capsule proteins
    C. producing repressor proteins to control the bacterial cell
    D. producing proteins that lyse the bacterial cell
    E. producing various enzymes to alter cellular metabolism

2. The function of reverse transcriptase in retroviruses is to
    A. hydrolyze the host cell's DNA
    B. use viral RNA as a template for DNA synthesis
    C. convert host cell RNA into viral DNA
    D. translate viral RNA into proteins
   E. use viral RNA as a template for making complementary RNA strands

3. Viruses have some of the properties of living organisms. Which of the following is characteristic of all
        organisms, but NOT of viruses?
    A. genetic information stored as nucleic acid
    B. ability to control metabolism
    C. ability to reproduce
    D. structure includes proteins
   E. plasma membrane

4.  Bacteriophage DNAs that have become integrated into the host cell chromosome are called
    A. Intemperate bacteriophages
    B. mutations
    C. Prophages
    D. T-even bacteriophages
    E. recombinant viruses

5. Which type of virus below would have a gene for the production of reverse transcriptase?
    A. A virus with double-stranded RNA as it’s genome
    B. A virus with single-stranded DNA as it’s genome
    C. A virus with double-stranded DNA as it’s genome
    D. A T2 bacteriophage
    E. A virus without a membranous envelope surrounding the capsid

6. Select that statement from below that is true for transposable genetic elements or transposons
    A. DNA sequences that can move from one plasmid to another at sites with specific nucleotide sequences
    B. DNA sequences that aid bacterial cells in antiobiotic resistance
    C. DNA sequences that move from one bacterial cell to another during transduction
    D. DNA sequences in bacteria chromosomes that originated from a virus infection
    E. DNA sequences in bacteria than can move freely between plasmids, from plasmids to chromosomes, and from one position on the
        chromosome to another aided by the enzyme transposase

7. Plasmids of bacteria often have genes involved in:
    A. redproduction
    B. motility
    C. viral resistance
    D. antibiotic resistance
    E. transduction

8.  The specificity or host range of viruses to different types of cells is due to ___________ sites on the host cell.
    A. prophage
    B. receptor
    C. conjugation
    D. transcription
    E. prions

9. A fun way to describe sex in the bacteria colony might be
A. Their plasmids were of the appropriate signs and so they conjugated their love for each other
B. The two cells agreed to enter into a transduction agreement first
C. It was a transformational experience for both cells
D. The two cells transposonated the afternoon away
E. The cells were unable to fuse because one cell went binary instead.
 

CHAPTER 16 REVIEW QUESTIONS

1.  Which region for a gene in DNA includes the binding site for RNA polymerase?
    A. the major groove
    B. the coding region
    C. promoter sequence
    D. the enhancer element sequence
    E.  the sequence between the trailer and the terminator

2. In a nucleosome, what is the DNA wrapped around?
    A. polymerase molecules
    B. ribosomes
    C. mRNA
    D. histones
    E. nucleolus protein

3. Most of the DNA in eukaryotic chromosomes is
   A. organized into operons
    B. highly repetitive DNA
    C. moderately repetitive DNA
    D. single-copy DNA sequences that are never transcribed
    E. single-copy DNA sequences that are repeatedly transcribed

4.  All of the following are potential control mechanisms for regulation of gene expression in eukaryotic organisms EXCEPT
    A. the degradation of mRNA
    B. the transport of mRNA from the nucleus
    C. transcription
    D. mRNA processing
    E. transformation

5.  The processing of the RNA transcript involves
    A. the removal of introns and the splicing together of exons
    B. the removal of exons and the splicing together of introns
    C. the addition of a guanine cap (5' cap) and a poly A tail
    D. the attachment of introns to ribosomal RNA
    E. Both A and C are correct

6.  A cell may meet the need for large quantities of a specific protein by
    A. continuously synthesizing the mRNA molecule that specifies the protein
    B.  increasing the half-life of the mRNA that specifies the protein
    C. having multiple copies of the gene that codes fo that protein
    D. all of the above
    E. none of the above

7. Which statement below accurately describes the lac Operon gene regulation system in E. Coli?
  A. used to produce lactose from glucose when lactose levels in the cell medium are very low
  B. genes are transcribed only when cyclic AMP is bound to a CAP activator and a lactose inducer binds to a repressor, keeping it from binding to an operator site
  C. genes are transcribed and used to process lactose when glucose levels in the cell are high
  D. transcription of the lac Operon is turned off when lactose molecules bind to the CAP binding site
  E. Used to convert lactose intolerant E. Coli cells into lactose tolerant E. Coli cells

8. Upstream promoter elements in eukaryotes are:
    A. nucleotide sequences that act as binding sites for RNA polymerase
    B. nucleotide sequences that regulate the efficiency of transcription initiation
    C. nucleotide sequences that contain the TATA box.
    D. proteins that enhance RNA polymerase binding to the promoter
    E. proteins that inhibit RNA polymerase binding to the promoter

9.  Which of the following statements about the regulation of gene expression in prokaryotes are false?
    A. genes can be turned on and off as environmental conditions change
    B. most gene regulation in prokaryotes occurs at the level of translation
    C. most gene regulation in prokaryotes occurs by DNA methylation to form euchromatin
    D. most gene regulation in prokaryotes occurs by transcriptional control
    E. All of the above
 

CHAPTER 19 REVIEW QUESTIONS:

1. PCR (polymerase chain reaction) is important because it allows us to:
    A. insert eukaryotic genes into prokaryotic plasmids
    B. incorporate genes into viruses
    C. make cDNA from RNA
    D. make many copies of DNA from a small sample
    E. insert regulatory sequences into eukaryotic genes.

2. Which of the following correctly describe gel electrophoresis
    A. Separates pieces of DNA based on size and chage
    B. involves insertion of DNA into plasmids
    C. DNA pieces are seen as bands
    D. includes modified bases that prevent further DNA synthesis
    E. Both A and C

3.  An RFLP (restriction fragment length polymorphism) is produced by:
    A. treating DNA with restriction enzymes.
    B. electrophoresis of restriction fragments
    C. dideoxynucleotides from DNA sequencing
    D. mutation of cDNA’s
    E. choices “a” and “b” above.

4. Which of the following  is usually not used in DNA fingerprinting analyses?
   A. PCR
    B. DNA sequencing analyses
    C. Gene cloning
    D. Electrophoresis
    E. Primers

5. Bacteria methylate their DNA in order to:
    A. prepare for DNA replication
    B. prepare for mitosis
    C. effectively infect other cells
    D. protect it from restriction enyzmes
    E. prevent viral DNA from hybridzing with bacterial DNA

6.  Associated with gene technology, please select the choice that DOES NOT accurately describe screening
when gene cloning is done using an antibiotic resistance transfer plasmid
  A. The key step used to identify bacteria cells that have taken up the recombinant plasmid by transduction
  B. The key step used to identify bacteria cells that have taken up the recombinant plasmid by transformation
  C. Can be done directly using radioactively labeled nucleotides
  D. can be done indirectly by identifying E. Coli cells that fail to grow on a medium including antiobiotics when the
        restriction enzyme site on the plasmid was within a gene sequence for antibiotic resistance
  E. can be done indirectly by identifying E. Coli cells that grow on a medium including antiobiotics when the
        restriction enzyme site on the plasmid was not within a gene sequence for antibiotic resistance

7.  The amplification of recombinant plasmids occurs by:
    A. the growth of the plasmid DNA
    B. the process of growth and division of the host cell.
    C. DNA replication of plasmids outside the host cell
    D. transformation of bacterial cells
    E. the polymerase chain reaction

8. What is the function of restriction nucleases in bacteria cells?
   A. Sort of like foreign DNA detectives; recognize and degrade foreign DNA introduced into the cell
   B. Change receptor sites so as to protect the bacteria from viral infection
   C. Aid in integrating plasmids back into the bacteria chromosome
   D. Restrict the attachment of viruses to receptor proteins in the cell membrane
   E. Sort of like bouncers, they restrict entrance of foreign viral genomes into the cell by checking
     viruses for DNA or RNA genomes and only DNA type genomes are allowed in

9. Which of the following enzymes joins the paired sticky ends of DNA fragments?
      A reverse transcriptase
      B. restriction enzymes
      C. DNA ligase
      D. DNA polymerase
      E. transferase
 

CHAPTER 21 REVIEW QUESTIONS:

1. Which of the following elements of Darwinism is associated with Malthus?
    A. artificial selection improves plant and animal breeds
    B. differential reproductive success is the cornerstone of natural selection
    C. the potential for population growth exceeds what the environment can support
    D. species become better adapted to their local environments through natural selection
    E. favorable variations accumulate in a population after many generations of natural selection

2. Which of the following best describes the fossil record?
    A. similar fossils are found in varying environments at different times
    B. there is a progression, with older fossils being primitive and younger fossils being advanced
    C. life has remained essentially unchanged since it began 6000 yrs ago
    D. all vertebrate classes make their first appearance in the fossil record in rocks of the same age
    E. the fossil record proves Darwin's hypothesized genetic variation in populations

3. One finds that organisms on islands are different from, but closely related to, similar
forms found on the nearest continent. This is taken as evidence that
    A. islands forms and mainland forms descended from common ancestors
    B. common environments are inhabited by the same organisms
    C. the islands were originally part
    D. the island forms and mainland forms are converging
    E. island forms and mainland forms share the same gene pool?

4. Catastrophism was Cuvier's attempt to explain
    A. evolution
    B. the fossil record
    C. uniformitarianism
    D. the origin of new species
    E. natural selection

5. The statement "improving the intelligence of an adult through education will result in that adult's
descendents being born with a greater native intelligence" is an example of
    A. Darwinism
    B. Lamarckism
    C. neo-Darwinism
    D. Natural Theology
    E.polygenic inheritance

6.  Evolution is genetic change in a(an) _____________________  that occurs over time
    A. individual
    B. population
    C. community
    D. ecosystem
    E. virus

7.  Darwin’s and Lamark’s theories of evolution both suggest that
    A. the interaction of organisms with their environment is important in the evolutionary process
    B. species are fixed
    C. the Earth is 6000 yrs old
    D. the environment creates favorable characteristics on demand
    E. the main mechanism of evolution is the inheritance of acquired characteristics

8.  Anatomical features that are derived from the same structure in a common ancestor but vary in
current function are said to be
    A. homologous
    B. primitive
    C. vestigial
    D. shared features
    E. recycled

9.  Which of following is not part of Darwin's concept of evolution
    A. a population is capable of producing more offspring than the environment can support
    B. individuals that are best adapted to their environment are more likely to survive and reproduce
    C. a struggle for existence exists among individuals of a population
    D. traits acquired during an individuals life are passed on to its offspring
    E. individuals in a population are genetically variable
 

CHAPTER 20 REVIEW QUESTIONS:

1. In a population with two alleles, A and a, the frequency of a is 0.6. What would be the frequency of
heterozygotes if the population is in Hardy-Weinberg equilibrium?
    A. 0.16
    B. 0.36
    C. 0.40
    D. 0.48
    E. 0.64

2. A founder event favors microevolution in the founding population mainly because
    A. mutations are more common in a new environment
    B. a small founding population is subject to extensive sampling error in the composition of its genepool
    C. the new environment is likely to be patchy, favoring diversifying selection
    D. gene flow increases
    E. members of a small population tend to migrate

3. As a mechanism of microevolution, natural selection can be most closely equated with
    A. assortative mating
    B. genetic drift
    C. differential reproductive success
    D. mutation
    E. gene flow

4.  In a population that is in Hardy-Weinberg equilibrium, the frequency of the allele a is 0.3. What is
the percentage of the population that is homozygous for this allele?
    A.  3%
    B.   9%
    C. 21%
    D. 30%
    E. 42%

5.  A thin-shelled crab can move more readily to escape from predators than can a thick-shelled crab, but it
is more vulnerable to predators that drill through the shell.  As a result of these opposing forces, shell
thickness for many types of crabs has remained within a narrow range over a long time.   What type of natural
selection does crab shell thickness illustrate?
    A. Diversifying selection
    B. Genetic Drift
    C. Stabilizing selection
    D. Disruptive selection
    E. Directional selection

6.  During the 1920s to 1940s, biologists combined Mendelian genetics with Darwin's theory to form a unified
explanation of evolution, which is referred to as
    A. classical Darwinism
    B. evolutionary genetics
    C. genetic evolution
    D. neo-evolution
    E. the synthetic theory of evolution

7.  Seriously abnormal phenotypes or harmful mutations are acted against or reduced to low frequencies by:
    A. natural selection
    B. gene flow
    C. directional selection
    D. genetic polymorphism
    E. genetic drift

8.  Mutations that are not passed on from one generation to the next:
    A. result from disruptive selection
    B. are balanced polymorphisms
    C. occur in somatic cells
    D. result from the founder effect
    E. are due to heterozygote advantage

9.  In the human species, heterozygote advantage is demonstrated by which condition?
    A. hemophilia
    B. sickle cell anemia
    C. Down syndrome
    D. Yellow fever
    E. birth weights around 7 lbs.
 

CHAPTER 22 REVIEW QUESTIONS:

1. Global climate change may be a significant problem for the maintenance of biodiversity because
     A. Plants & animals may be unable to evolve fast enough to keep up with environmental changes
     B. Butterflies are unable to reproduce in warmer climates
     C. Evolution by natural selection will proceed at a different pace as weather patterns change
     D. Gradual changes in populations of species will accumulate faster than before
     E. Plants and animals will move to new areas where they will be able survive and reproduce

2.  The process of a new species arising within the range of the parent population is termed
    A. semispeciation
    B. adaptive radiation
    C. sympatric speciation
    D. parapatric speciation
    E. allopatric speciation

3.  Which of the following is the most likely pattern for the origin of species?
    A. anagenesis
    B. cladogenesis
    C. phyletic evolution
    D. spontaneous generation
    E. inheritance of acquired characteristics

4.  Which of the following reproductive isolating mechanisms is postgygotic
    A. Habitat isolation
    B. temporal isolation
    C. hybrid sterility
    D. behavioral isolation
    E. gamete incompatibility

5. A characterisitic of allopatric speciation is
    A. the appearance of new species in the midst of old ones
    B. asexually reproducing populations
    C. artificial selection
    D. geographic isolation
    E. large populations

6.  The model that maintains that populations diverge from one another by the slow accumulation of
adaptive characteristics within each population is:
    A. gradualism
    B. allopolyploidy
    C. punctuated equilibrium
    D. hybridization
    E. macroevolution

7.  New ecological roles that were not previously exploited by an ancestral organism are referred to as
    A. sympatic speciation
    B. adaptive radiation
    C. adaptive zones
    D. allopatric speciation
    E.  microevolution

8. When the reproductive cells of different species are incompatible, it is referred to as:
    A. behavioral isolation
    B. gametic isolation
    C. hyrbid breakdown
    D. hyrbid sterility
    E. mechanical isolation

9. Which of the following is NOT a true statement regarding why natural selection is unable to produce
perfectly adapted organisms
    A. Natural selection acts on the phenotype which can be significantly influenced by the environment
    B. The environment is not constant
    C. Organisms have a long history of modification by descent, so entirely new designs are not possible
    D. New allele combinations can be produced as a result of natural selection
    E. Adaptations are compromises among competing needs