Genetics Exam #2
In a transversion mutation, A. a pyrimidine substitutes for a purine. B. a purine substitutes for a purine. C. a single nucleotide is inserted D. a translocation occurs.
A. a pyrimidine substitutes for a purine.
Nonhomologous end-joining" is A. a way of repairing a DNA double-strand break and is often error-prone. B. very similar to base excision repair C. defective in Xeroderma Pigmentosum D. a way of repairing AP sites.
A. a way of repairing a DNA double-strand break and is often error-prone.
The process known as RNA editing A. occurs in two general ways: substitution editing and insertion/deletion editing B. silences gene expression through the use of "guide RNA" C. is the process of splicing out introns D. is also known as "RNA interference"
A. occurs in two general ways: substitution editing and insertion/deletion editing
Which statement is true? A. All DNA has the structure of "B DNA" all of the time. B. DNA is usually in the form of a left-handed helix. C. Structurally, the two strands of DNA in a helix have the same polarity. D. As a rule, a higher GC content means a higher melting point for a DNA helix.
As a rule, a higher GC content means a higher melting point for a DNA helix.
The condition known as cri-du-chat syndrome in humans has a genetic constitution designated as A. 45, X B. 46, 5p- C. 47, 21+ D. 47, 13+
B. 46, 5p-
The equation L = T + W has something to do with A. DNA supercoiling B. Mendel's experiments C. balanced translocations D. None of the above
DNA supercoiling
Two major classifications of transposable elements in the human genome are A. SINEs and satellites B. VNTRs and STRs C. Copia and P elements D. DNA transposons and retrotransposons
DNA transposons and retrotransposons
The individual whose karyotype is shown below is: (two X chromosome, 1 Y) A. is female B. displays triploidy C. displays aneuploidy D. all of the above
Displays Triploidy
The basic structure of a nucleotide includes which of the following components? A. amino acids. B. base, sugar, phosphate. C. phosphorous and sulfate. D. all of the above.
base, sugar, phosphate
Forms of inheritance that do not follow typical Mendelian patterns and that appear to be more influenced by the parent contributing the most cytoplasm to the embryo can most appropriately be grouped under the general heading of A. sex-linked inheritance B. extrachromosomal inheritance C. suppressive inheritance D. dominance and/or recessiveness
extrachromosomal inheritance
The genotype XXYY should produce a: A. female in Drosophila and a female in humans. B. female in Drosophila and a male in humans. C. male in Drosophila and a male in humans. D. male in Drosophila and a female in humans.
female in drosophila and male in humans
A mutation resulting in multiple amino acid changes that really mess up a protein is likely a(n) A. frameshift. B. base substitution. C. transversion. D. insertion of 3 nucleotides.
frameshift
Consider the two DNA helices shown to the right. Which helix best represents the structure of DNA most likely to be found in a living cell A. helix i B. helix ii C. either one is equally likely. D. neither one since DNA alternates in its handedness.
helix i
Chromatin of eukaryotes is organized into repeating interactions with protein octomers called nucleosomes. Nucleosomes contain which class of protein molecules? A. histones B. glycoproteins C. lipids D. nonhistone chromosomal proteins
histones
The strands of a DNA helix are held together to each other by A. covalent bonds. B. hydrogen bonds. C. phosphodiester bonds. D. glycosidic bonds.
hydrogen bonds
The simplest transposable elements in bacteria are known as A. transposons. B. insertion sequences. C. Ds elements. D.cCopia elements.
insertion sequences
In the figure to the right depicting a functional insertion sequence from bacteria, the sequence labeled "internal sequence"// labeled "X A. codes for telomerase B. codes for reverse transcriptase C. codes for transposase D. are telomeric repeats
internal- codes for transposes X- are inverted terminal repeats
the figure on the right depicts formation of:
reciprocal translocation
Consider the equation L = T + W which describes supercoiling of a DNA molecule. If L is equal to T for a certain DNA molecule, then that DNA molecule is A. negatively supercoiled B. positively supercoiled C. relaxed D. linear
relaxed
Ultraviolet light causes pyrimidine dimers to form in DNA. Some individuals are genetically incapable of repairing dimers at normal rates. Such individuals are likely to suffer from A. phenylketonuria. B. muscular dystrophy. C. Huntington disease. D. skin cancer
skin cancer
A figure on right depicts formation of A. chromosomal inversion B. nonreciprocal translocation C. a structure that will probably lead to semisterility D. normal meiotic crossover event
structure that will probs lead to semisterility
Consider the experimental results shown to the right. This data provides reason to believe that A. DNA is not the genetic material. B. protein is the genetic material. C. both DNA and protein serve as genetic material. D sunblock is a good idea.
sunblock is good idea
The enzyme that appears to be inappropriately expressed in cancer cells and helps to prevent the ends of eukaryotic chromosomes from getting shorter with each round of replication is called A. topoisomerase. B. ligase. C. telomerase. D. terminase.
telomerase
When it comes to X chromosome inactivation in a human cell, transcription of the XIST gene is enhanced on A. the X chromosome that will be inactivated. B. the active X chromosome. C. both X chromosomes. D. neither X chromosome.
the X chromosome that will be inactivated
In humans, the genetic basis for determining the sex "male" is accomplished by A. precedes of Y chromosome B. the presence of only one X chromosome C. a balance between the number of X chromosomes and the number of haploid sets of autosomes D. multiple alleles scattered throughout the autosomes
the Y chromosome
Satellite sequences are usually found in A. the centromeric region. B. the coding region of genes. C. the introns of genes. D. bacterial genomes.
the centromeric region
The fact that there is a problem maintaining the very ends of eukaryotic chromosomes during replication has to do with A. the fact that eukaryotic chromosomes are circular. B. the inability of DNA polymerases to initiate synthesis without an RNA primer. C. the restriction that DNA synthesis must occur in a 3' to 5' direction. D. all of the above.
the inability of DNA polymerases to initiate synthesis without an RNA primer.
The DNA repair pathway that starts with the action of a DNA glycosylase to remove a base is A. nucleotide excision repair B. photoreactivation C. base excision repair D. mismatch repair
base excision reapir
Hemophilia is caused by a sex-linked recessive gene. If a man with hemophilia marries a normal woman whose father had hemophilia, what is the probability that they will have a son with hemophilia? (Note: in this problem you must include the probability of having a son in your computation of the final probability.)
1/4
What is the expected number of Barr bodies in an individual with the karyotype XXXXYY?
3
If 20% of the nitrogenous bases in a sample of DNA from a particular organism is thymine, what percentage should be cytosine? A. 15% B. 30% C. 40% D. 35%
30%
32P and 35S were used in the classic experiment conducted by Hershey and Chase because A. 32P labels DNA and 35S labels protein B. 32P labels protein and 35S labels DNA C. both radioisotopes label an entire phage including DNA and protein D. 32P labels DNA and 35S labels RNA
32P labels DNA and 35S labels protein
A somatic cell from a human displaying a tetrasomy would contain a total of how many chromosomes? A. 46 B. 47 C. 48 D. 49
48
A somatic cell from a triploid person contains a total of how many chromosomes?
69
A somatic cell from a triploid person contains how many centromeres during the G1 phase of the cell cycle? A. 69 B. 92 C. 47 D. 49
69
A somatic cell from a tetraploid person contains a total of how many chromosomes? A. 69 B. 92 C. 4 D. 47
92
Familial Down syndrome is caused by A. position effect. B. nondisjunction. C. a centric fusion. D. a segmental deletion.
A centric Fusion OR Roberstsonian translocation
Which of the following represent three posttranscriptional modifications often seen in the maturation of mRNA in eukaryotes? A. 3'-capping, 5'-poly(A) tail addition, splicing. B. removal of exons, insertion of introns, capping. C. 5'-capping, 3'-poly(A) tail addition, splicing. D. 5'-poly(A) tail addition, insertion of introns, capping.
C. 5'-capping, 3'-poly(A) tail addition, splicing.
An abnormal chromosome containing two genetically identical arms is called A. a centric fusion B. an inversion chromosome C. an isochromosome D. a ring chromosome
C. an isochromosome
The "wobble hypothesis" A. has to do with gene expression leading to metastasis. B. partially explains chromatin remodeling. C. helps explain degeneracy in the genetic code.. D. provides a reason to avoid heavy drinking.
C. helps explain degeneracy in the genetic code.
A "three - parent baby" refers to a baby for which A. two parents contribute mitochondria, and a third contributes the nuclear genome, B. one parent contributes mitochondria, one contributes chloroplasts, and one contributes the nuclear genome. C. two parents each contribute a haploid genome from their gametes while mitochondria are contributed by a third individual D. behavior is so poor that it takes a third parent to help raise the child.
C. two parents each contribute a haploid genome from their gametes while mitochondria are contributed by a third individual
Which statement is true? A. DNA damage and mutation are the same thing. B. DNA damage is defined as a permanent change in the nucleotide sequence. C. DNA damage always leads to mutation. D. DNA damage can lead to mutation, but doesn't always.
D. DNA damage can lead to mutation, but not always
The presence of transposons in a genome can potentially have an impact on gene expression by A. altering chromatin and inducing gene silencing B. disrupting a gene by inserting into a coding region C. creating the potential for aberrant chromosomal rearrangements D. all of the above
D. all of the above
If an organism is heterozygous for a chromosomal inversion, then A. a condition of "semisterility" will occur in the absence of any crossing over. B. the organism must be phenotypically abnormal C. chromosome number is likely altered D. meiotic crossovers within the inverted interval will not be recovered in offspring.
D. meiotic crossovers within the inverted interval will not be recovered in offspring.
Which of the following clusters of terms accurately describes DNA as it is generally viewed to exist in prokaryotes and eukaryotes? A. Double-stranded, parallel, (A+T)/(C+G)= variable, (A+G)/(C+T)=1.0 B. Single-stranded, antiparallel, (A+T)/(C+G)=1.0, (A+G)/C+T)=1.0 C. Double-stranded, antiparallel, (A+T)/C+G)=1.0, (A+G)/(C+T)=variable D. Double-stranded, antiparallel, (A+T)/(C+G)=variable, (A+G)/(C+T)=1.0
Double-stranded, antiparallel, (A+T)/(C+G)=variable, (A+G)/(C+T)=1.0
Which of the following statements is true? A. For all organisms, sex is determined by a set of sex chromosomes. B. Males are always the "heterogametic" sex. C. For some organisms, sex is determined by the temperature during embryonic development. D. None of the above
For some organisms, sex is determined by the temperature during embryonic development.
Which of the following is a type of transposable element found in the human genome? A. SIGNs. B. LINEs C. Copia D. P elements.
LINEs
a "three-parent baby" refers to a baby for which: A. two parents contribute mitochondria, and a this contributes the nuclear genome B. one parents contributes mitochondria, on contributes chloroplast, and one contributes nuclear genome C. one parent contributes a complete diploid genome, one parent contributes cytoplasm, and one contributes mitochondria D. none of the above
None of the above
if an organism is heterozygous for chromosomal inversion, then: A. 50% sterility B: will likely be visibly normal C. Meiotic crossovers within the introverted interval are recovered at a high frequency D. none of the above
None of the above
Which of the following is NOT considered to be a tandem repeat A. satellite sequences B. telomeric repeats C. SINES D. VNTRs
SINES
The individual who's karyotype is shown here is: (one X chromosome A. has Klinefelter syndrome. B. has Turner syndrome C. displays euploidy D. is phenotypically male
Turners Syndrome
Which statement is true? A. DNA damage and mutation are the same thing. B. DNA damage almost always goes unrepaired. C. a mutation is defined as a permanent change in the nucleotide sequence. D. mutations are always caused by DNA damage. A. DNA damage and mutation are the same thing. B. DNA damage almost always goes unrepaired. C. a mutation is defined as a permanent change in the nucleotide sequence. D. mutations are always caused by DNA damage.
a mutation is defined as a permanent change in the nucleotide sequence.
In a transition mutation, A. a pyrimidine substitutes for a purine. B. a purine substitutes for a purine. C. a single nucleotide is inserted D. a translocation occurs.
a purine substitutes for a purine.
An abnormal chromosome in which the ends of the two arms are fused together is A. a centric fusion B. an inversion chromosome C. an isochromosome D. a ring chromosome
a ring chromosome
the figure to the right depicts:
a robertsonian translocation
nonhomologous end joining A. a way of repairing a DNA double-strand break and is often error-prone. B. very similar to base excision repair C. defective in Xeroderma Pigmentosum D. a way of repairing AP sites.
a way of repairing a DNA double-strand break and is often error-prone
The fact that there is a problem maintaining the very ends of eukaryotic chromosomes during replication has to do with A. the fact that eukaryotic chromosomes are linear. B. the inability of DNA polymerases to initiate synthesis without a primer. C. the restriction that DNA synthesis must occur in a 5' to 3' direction. D. all of the above.
all of the above
The fact that there is a problem maintaining the very ends of eukaryotic chromosomes during replication has to do with A. the fact that eukaryotic chromosomes are linear. B. the inability of DNA polymerases to initiate synthesis without a primer. C. the restriction that DNA synthesis must occur in a 5' to 3' direction. D. all of the above.
all the above
tautomeric shift A. is typically induced by high-energy radiation. B. alters base-pairing. C. can lead to a transversion mutation. D. occurs only in prokaryotes.
alters base-pairing
A "Barr body" is: A. a gene on the X chromosome that is responsible for female development. B. a patch of cells that has a phenotype different from surrounding cells because of variable X inactivation C. an inactivated Y chromosome, visible in the nucleus of a cell from a male mammal. D. an inactivated X chromosome, visible in the nucleus of a cell from a female mammal.
an inactivated X chromosome, visible in the nucleus of a cell from a female mammal.
When an organism gains or loses one or more chromosomes but not a complete haploid set, the condition is known as A. polyploidy B. aneuploidy C. triploidy D. trisomy
aneuploidy
Microsatellite DNA sequences A. are present in one copy per haploid genome B. are completely deleted in Patau syndrome C. resemble tiny weather satellites D. are present in eukaryote genomes as tandem repeats of a very short sequence
are present in eukaryote genomes as tandem repeats of a very short sequence
What does the term heteroplasmy refer to? A. cells with a variable mixture of normal and abnormal organelles B. heterozygous individuals with more than one gene pair involved C. various stages of development of mitochondria and chloroplasts D. none of the above
cells with a variable mixture of normal and abnormal organelles
The genetic material of most living things A.deoxy B. ribonucleic acid. C. RNA. D. polysaccharide.
deoxyribonucleic acid
A fertilized egg inherited one X and one Y chromosome, but after several rounds of cell division in embryo a cell is produced that has lost Y chromosome. Which of the following is a possibility regarding the individual that develops from this embryo? A. person is a hermaphrodite B. person displays Turners Syndrome C. persons has little or no phenotype D. each is a possibility
each is a possibility
In Luria and Delbruck's classic experiments to distinguish between "random" versus "adaptive" mutation, A. evidence for random mutation was produced. B. evidence for adaptive mutation was produced. C. evidence that DNA is the genetic material was produced. D. all of the above.
evidence for random mutation was produced
consider the following figure, it depicts
example of unequal crossing over
Diseases associated with "genetic anticipation" are often caused by A. insertion of foreign DNA into a chromosome. B. expansion of trinucleotide repeats C. multiple inversions in the X chromosome. D. single translocations in the X chromosome.
expansion of trinucleotide repeats
Based on the experiment shown in the figure to the right It can be concluded that compound "X" is likely A. a mutagen B. not a mutagen C. a liver enzyme D. an intercalating agent
mutagen
A calico cat A. is produced by equal expression of genes on both X chromosomes in a cell B. is female. C. is male. D. none of the above.
is female
Gene dosage compensation A. is needed when one sex has fewer copies of a gene or genes than the other sex. B. is a problem in species that have more autosomes than sex chromosomes. C. cannot be accomplished by enhancing X-chromosome activity. D. works in the same way in all animals.
is needed when one sex has fewer copies of a gene or genes than the other sex
refer to replication fork: Item A is and Item B is
item A is Okazaki fragment (entire line) item B is an RNA primer (bolded) item C stretch of RNA
A balanced translocation: A. leads to the condition of "semisterility" even in the absence of any crossing-over. B. leads to semisterility only if a crossover occurs between the translocated chromosomes during meiosis. C. greatly increases the chances of nondisjunction. D. is lethal.
leads to the condition of "semisterility" even in the absence of any crossing-over.
Griffith's classic experiments with mice and Diplococcus pneumoniae A. demonstrated that DNA is the genetic material. B. demonstrated that the genetic material is not protein. C. led to the discovery of the "transforming principle." D. all of the above.
led to the discovery of the "transforming principle."
The genotype X0 produces a A. female in Drosophila and a female in humans. B. female in Drosophila and a male in humans. C. male in Drosophila and a male in humans. D. male in Drosophila and a female in humans.
male in Drosophila and a female in humans.
The genotype XYY produces a A. female in Drosophila and a female in humans. B. female in Drosophila and a male in humans. C. male in Drosophila and a male in humans. D. male in Drosophila and a female in humans.
male in drosophila and male in humans
In the snail Lymnaea peregra, the pattern of shell coiling is determined by the genotype of the egg-producing parent regardless of the phenotype of that parent. This type of inheritance is best referred to as: A. sex-linked inheritance B. mitochondrial inheritance C. maternal effect, or maternal influence D. haploinsufficiency
maternal effect or maternal influence
During mismatch repair in bacteria, the newly synthesized strand is distinguished from the old strand by A. a strand break on the old strand. B. methylation on the new strand. C. methylation on the old strand. D. nothing; the strands cannot be distinguished.
methylation on the old strand
a mutation is defined as a permanent change in the nucleotide sequence. A. a strand break on the old strand. B. methylation on the new strand. C. methylation on the old strand. D. the new strand always contains the purine
methylation on the old strand
Which of the following organelles are involved in the general category of organelle heredity? A. mitochondria and chloroplasts B. golgi and nuclei C. lysosomes and peroxisomes D. golgi and rough endoplasmic reticulum
mitochondria and chloroplasts
one explanation for detectable organelle inheritance is that: A. mitochondria and chloroplasts lack DNA and are therefore dependent on the maternal cytoplasmic contributions B. mitochondria and chloroplasts have DNA that is subject to mutation C. organelles such as mitochondria are always wild type D. chloroplasts, for example, are completely dependent on the nuclear genome for components
mitochondria and chloroplasts have DNA that is subject to mutation
what is the most likely mode of inheritance for the pedigree below? (female has trait and all of off spring)
mitochondrial
With regard to eukaryotic chromatin, when one visualizes "beads-on-a-string" each bead is A. gene. B. single histone. C. nucleosome. D. solenoid.
nucleosome
The DNA repair process depicted in the figure to the right is called A. mismatch repair B. homologous recombination (HR) C. base excision repair D. nucleotide excision repair
nucleotide excision repair
The observation that a fly heterozygous for the double Bar allele and the wild-type allele (genotype = BD/B+) has a different phenotype than a fly that is homozygous for the Bar eye allele (genotype = B/B) serves as an example of the phenomenon known as A. chaos B. position effect C. incomplete penetrance D. inversions
position effect
in humans the genetic basis for deterring sex "male" is accomplished by: A. an autosome B. the number of X chromosomes C. the presence of the SRY gene D. a balance between the number of X chromosomes and the number of haploid sets of autosomes
presence of SRY gene
Consider the experimental results shown to the right. This data provides evidence that: (absorption spectrum of nucleic acid and protein seperate peaks) A. DNA is not the genetic material. B. protein is not the genetic material. C. both DNA and protein serve as genetic material. D. hanging out in the sun is a good idea.
protein is not the genetic material // DNA is the genetic material//sunscreen good idea
A fertilized egg inherited one X and two Y chromosomes, but in a subsequent round of cell division in the embryo a cell is produced that has lost one Y chromosome. Which of the following is a likely possibility regarding the individual that develops from this embryo? A. the person may be a hermaphrodite B. the person has mosaic Turner Syndrome C. the person may actually have a very mild phenotype. D. all of the above are likely.
the person may actually have a very mild phenotype
The terms "spindle transfer" and "pronuclear transfer" have something to do with A. "three-parent" babies B. steps in mitosis C. types of chromosomal rearrangements D. gel electrophoresis
three-parent babies
An enzyme that controls supercoiling in DNA is called A. telomerase B. polymerase C. reverse transcriptase D. topoisomerase
topoisomerase
When a diploid organism gains a complete haploid set of chromosomes, the condition is known as A. monoploidy B. aneuploidy C. triploidy D. trisomy
triploidy
Ultraviolet light causes pyrimidine dimers to form in DNA. Some individuals are genetically incapable of repairing dimers at normal rates. Such individuals are likely to suffer from A. xeroderma pigmentosum. B. phenylketonuria. C. muscular dystrophy. D. Huntington disease.
xeroderma pigmentosum
