Which of the following human cells contains a gene that specifies eye color?
a. Cells in the eye.
b. Cells in the heart.
c. Gametes (sperm and egg).
d. Cells in the eye and gametes.
e. All of the above.
e
An inherited disease that affects women and not men is likely to be caused by:
a. a mutation in a gene on the X chromosome, which is a sex chromosome.
b. a mutation in a gene on a non-sex chromosome (autosome).
c. without additional information, either an
c
An isolated population of prairie dogs has longer than average teeth. As a result they can eat more grass with less effort and are better able to survive. The mutation(s) that resulted in longer teeth:
a. allowed the teeth to grow longer over several gene
c
Starting with a population of genetically identical mice, you discover two new independent mutant strains in which all of the animals have epileptic seizures. In both strains, you know that the epileptic seizures are due to a single DNA mutation. You cros
b
A young man develops skin cancer that does not spread to any other tissues; the mutation responsible for the cancer arose in a single skin cell. If he and his wife (who does not have skin cancer) have children after the skin cancer diagnosis, which of the
d
The MLH1 gene is located on chromosome 3 in humans and four different alleles have been identified. The maximum number of alleles a single normal individual can have is:
a. 1
b. 2
c. 3
d. 4
b
A population of buffalos is isolated such that no new buffalos can come into their territory. Which of the following is primarily responsible for the appearance of new alleles in this population?
a. Reassortment of chromosomes during the process of creati
b
Cystic fibrosis in humans is caused by mutations in a single gene and is inherited as an autosomal (non-sex chromosome) recessive trait. A normal couple has two children. The first child has cystic fibrosis, and the second child is unaffected. What is the
c
You have identified a previously unknown human gene that appears to have a role in autism. It is similar enough in DNA sequence to a known mouse gene that you believe the two genes may be evolutionarily related. You determine and compare the DNA sequences
c
Cells in the king crab have 104 pairs of chromosomes. You have discovered another similar looking species of crab that you call the prince crab, which has only 100 pairs of chromosomes in its cells. From this finding, you can conclude that:
a. the king cr
e
A woman who is a carrier for X-linked hemophilia (she does not have the disease) marries a man who does not have hemophilia. They have a daughter, named Angela, who does not have the disease. Angela marries George, who also does not have hemophilia. Angel
b
Polydactyly is an inherited trait that results in extra fingers or toes. In the United States 0.1% of the population exhibits polydactyly. People with polydactyly have the genotype Pp, where P represents the allele that causes polydactyly and p represents
b
You are interested in studying a gene called CFTR because mutations in this gene in humans cause cystic fibrosis. You have made a line of mice that lack the mouse CFTR gene. These mice are unable to clear bacteria from their lungs, so they get lung diseas
c
In the cells of all human females, one X chromosome is inactivated. The opsin1 gene is on the X chromosome and is expressed in the retinal cells of the eye. Mutations in this gene cause the recessive trait of colorblindness. Most women who have one mutant
d
Small DNA tumor viruses such as SV40 and HPV have viral oncogenes that are not homologs of host cell genes. Some of these novel viral oncogenes make proteins that exert their tumorigenic effect by
a. binding to and inactivating pRB.
b. making Gag, Pol and
a
Familial hypercholesterolemia is a genetic disease that affects approximately one in 500 people worldwide. There is more than one genetic cause of the disease. Class I is often described as an autosomal dominant disease. Affected individuals have choleste
c
The chromosome of most prokaryotes differs from those of eukaryotes in that
a. the prokaryotic chromosome is linear, while the eukaryotic chromosome is circular.
b. the prokaryotic chromosome is circular, while the eukaryotic chromosome is linear.
c. the
b
Which form of DNA is a left-handed double helix?
a. A-DNA
b. B-DNA
c. L-DNA
d. R-DNA
e. Z-DNA
e
In class we discussed a case study about Abby, who suffered from a type of cancer that occurred due to mutation in protein that controlled cell cycle. What type of cancer did Abby have?
a. Breast Cancer
b. Liver Cancer
c. Ovarian Cancer
d. Testicular Canc
c
What is meant by an SNP haplotype?
a. a set of specific SNP alleles at particular SNP loci that is close together in one small region of a chromosome
b. a small group of genetically linked SNPs
c. a description of all of the SNPs present on one chromosome
c
Unintended environmental consequences are a serious challenge in the use of GM crops. For example, the use of Bt-corn, corn with genetically modified with a B.thuringiensis gene introducing insect-resistance, has had an effect on monarch butterfly populat
c
If the base pairs in a B DNA helix are 0.34 nm apart, and a complete (360�) turn of the helix takes 3.4 nm, how many base pairs per turn are there in a B DNA molecule ?
a. 1
b. 3.4
c. 10
d. 34
c
In a sunzilla sunflower plant that is heterozygous for seed color, what proportion of gametes will carry the recessive allele?
a. 1/4
b. 1/2
c. 3/4
d. 1/8
b
A person with type B blood could safely receive a transfusion of blood from someone with blood type
a. B.
b. AB.
c. O.
d. Both A and C
e. Any of these
c
Which of the following will result in modifications to the expected Mendelian ratios?
a. Epistasis
b. Incomplete dominance
c. Incomplete penetrance
d. Gene interaction
e. All of these
e
Cancer is best defined as
a. immune dysfunction.
b. uncontrolled and abnormal cell division.
c. viral malignancy.
d. regulated differentiation of tissue.
e. cellular deregulation.
b
Agents that can induce cancer through mutagenesis are called
a. destabilizers.
b. cancerogens.
c. mutagens.
d. carcinogens.
e. None of these
d
Cancer may arise as a result of
a. mutations associated with viral infection.
b. mutations associated with chemical mutagens.
c. mutations associated with radiation.
d. spontaneous mutations.
e. All of these
e
In a Sanger sequencing gel electrophoresis, which of the following DNA fragments would travel the farthest distance from the sample well?
a. ATCCCG
b. ATCC
c. AT
d. ATCCCGATTGCACGTT
c
In Sanger sequencing reactions, when a dideoxyribonucleotide is added to growing DNA strand
a. replication of the strand continues
b. replication of the strand stops
c. replication of the strand is not affected
d. replication of the strand is speeded up
b
What naturally occurring feature of the Ti plasmid makes it useful in genetic engineering of plants?
a. It occurs in plant chloroplasts.
b. It has a gene that encodes antibiotic resistance.
c. It is capable of introducing exogenous genes into plant genome
c
The closer together two genes are on a chromosome,
a. the more likely there will be a recombination event between them.
b. the less likely there will be a recombination event between them.
c. the greater the chance that a double crossover will occur betwe
b
Li-Fraumeni syndrome is a rare inherited disease that greatly increases a person's risk of developing several types of cancer. This disease stems from a mutation in the TP53 tumor suppressor gene. In most cases, approximately 95% of the mutations can be d
a
Genetic drift may lead to
a. loss of genetic variation in a population.
b. a decrease in the mutation rate of a particular gene.
c. increased heterozygosity at many loci.
d. Hardy-Weinberg equilibrium.
a
For alleles of genes in Hardy-Weinberg equilibrium, the frequency of heterozygotes is represented as
a. p.
b. q.
c. p2.
d. q2.
e. 2pq.
e
The Bcl-2 gene product in its normal form can be activated to prevent cells from undergoing apoptosis (programmed cell death) in specific circumstances. It is a carefully regulated gene, being "turned on" only under specific circumstances. A null mutation
b
If there are two alleles of a gene, B and b, and the frequency of the B allele (p) is 0.90, the frequency of the b allele (q) is
a. 0.81.
b. 0.30.
c. 0.10.
d. 0.09.
e. 0.01.
c
A(n) ________ inversion includes the centromere.
a. concentric
b. pericentric
c. paracentric
d. epicentric
e. chromocentric
b
A human cell containing two sets of 23 chromosomes is
a. aneuploid.
b. polyploid.
c. euploid.
d. haploid.
e. None of these
c
ABO blood type is determined by alleles that show
a. complete penetrance.
b. incomplete penetrance.
c. variable expressivity.
d. incomplete penetrance and variable expressivity.
a
Nondisjunction of chromosomes may result in
a. the loss of one homologous chromosome pair.
b. the addition of one homologous chromosome pair.
c. the addition of a single chromosome.
d. the loss of a single chromosome.
e. All of these
e
Individuals with neurofibromatosis may have a range of phenotypes, from pigment spots on the skin to tumorlike growths. This is an example of
a. incomplete penetrance.
b. variable expressivity.
c. age of onset.
d. X-inactivation.
...
Most monoploid individuals do not survive because
a. they do not have the appropriate gene dosages.
b. their cells cannot divide properly.
c. recessive lethal mutations cannot be masked by dominant alleles.
d. they have missing genes.
e. they have only on
c
Which of the following types of chromosomal mutation cannot revert to the wild-type state?
a. Duplication
b. Deletion
c. Translocation
d. Inversion
e. Any of these may revert to wild-type
b
During translation elongation, what order does a tRNA bind to the sites in the ribosome?
a. E site, P site, A site
b. A site, P site, E site
c. P site, E site, A site
d. A site, E site, P site
b
The drug GE81112 is suggested to inhibit 30S formation by directly blocking the binding of fMet-tRNA ^fMet . How might this affect the 80S ribosome in human cells versus the 70S subunit in prokaryotes and why?
a. GR81112 would not affect human ribosomes,
a
Which of the following nucleotide changes leads to a transvehrsion mutation?
a. Adenine to guanine
b. Adenine to cytosine
c. Guanine to adenine
d. Thymine to cytosine
b
Which of the following statements is correct? (I) An open reading frame always begins with AUG. (II) An open reading frame ends with a stop codon that is in frame (three nucleotides at a time) with the AUG start codon. (III) An open reading frame, also ca
a
Bt corn functions as a pesticide due to what protein product of Bacillus thuringiensis
a. sad protein
b. cry protein
c. sob protein
d. cro protein
b
Base analogs may cause mutations because
a. they modify the chemical structure and properties of the normal base
b. they insert themselves between adjacent bases on the DNA strand and cause an extra base to be inserted during replication
c. they remove am
d
Which of the following statements regarding Nucleotide Excision Repair and Base Excision Repair is true?
a. both NER and BER can be activated by exposure to visible light
b. only NER involves the action of DNA ligase to seal nicks in the DNA backbone
c. b
c
A transposon is
a, a DNA segment that can insert itself at one or more sites in a genome
b. a "jumping gene"
c. a DNA segment that may cause mutations in genes or chromosomal rearrangements
d. a mobile genetic element that may or may not leave a copy of i
e
Retrotransposons such as LINEs differ from typical transposons in that
a. retrotransposons are only found in prokaryotes, not eukaryotes
b. retrotransposons are transcribed to RNA, the back to DNA before insertion
c. retrotransposons always insertion into
b
In Drosophila, the wild-type eye color is red. A mutation, vermilion, causes vermilion-colored eyes, unless there is a mutation in another gene, suv which results in eyes that are the wild-type red even in the presence of the vermilion mutation. This is a
d
Photolyase enzyme involved in photoreactivation (light repair) can remove ______.
a. UV induced double strand breaks
b. mismatches in DNA
c. single strand breaks in DNA
d. UV induced thymine dimers
d
The function of UvrD in NER is ___.
a. to identify the lesion in the DNA
b. helices activity to unwind the DNA
c. to catalyze the incision at the 3' end of the lesion
d. to catalyze the incision at the 5' end of the lesion
b
An IS (insertion sequence) element contains
a. a transposes gene only
b. a transposes gene and additional genes
c. a transposes gene and inverted repeats at the ends
d. a transposes gene, additional genes, and inverted repeats at the ends
c
To make glyphosate resistant plants, cloned genes are first inserted within the ____ to generate a transgenic plant.
a. the Agrobacterium genome
b. the plant genome
c. the Ti plasmid
d. chloroplast of the plant
c
To inhibit the transcription of operon genes, the lacI gene product binds to
a. the operator
b. the promoter
c. the repressor
d. the inducer
a
True or False; A transposon may carry genes for proteins that enable their transposition as well as genes for other functions such as drug resistance.
True
True or False; If DNA is exposed to the deaminating agent nitrous acid, cytosine can be converted to uracil causing the C-G to T-A transition mutation
True
True or False; In methyl-directed mismatch repair, repair proteins distinguish between the correct parental strand and the mutated DNA strand by recognizing methylated sites on the mutated strand
False
True or False; LINEs and SINEs are repetitive sequences in humans that can also, as retrotransposons, insert into genes and cause disease.
True
True or False; Somatic mutations may be inherited by the next generation
False
In his experiments, Mendel noted that when two traits are involved in a genetic cross, they are inherited independently of each other. The reason for this is that
a. genes on the some chromosome separate during the formation of gametes
b. alleles on the s
c
Which of the following genotypes would represent a homozygous individual for the same gene?
a. AA
b. AB
c. Ab
d. ab
e. ab
a
In lilies, white flowers are dominate to purple flowers and smooth leaves are dominant to curly leaves. If two plants that are heterozygous for flower color and leaf texture are mated, the phenotypic ratio of the offspring would be
a. 3:1
b. 1:1
c. 1:2:1
d
In peas, tall plants are dominant to short plants. A cross between a tall pea plant and a short pea plant results in half the progeny being tall, and the other half being short. Therefore, the tall parent plant is genotypically
a. homozygous
b. heterozygo
b
The protein class(es) involved in the activation of transcription is (are)
a. general transcription factors
b. transactivators
c. coactivators
d. A and B only
e. A, B and C
e
In eukaryotic cells, steroid hormones
a. bind to cytoplasmic receptors, are transported to the nucleus, bind DNA, and regulate gene expression
b. bind to cell surface receptors and send signals that result in regulation of genes in the nucleus
c. act as e
a
Unlike prokaryotes, most gene regulation in eukaryotes
a. takes place at the transcriptional level.
b. is controlled at the level of transcript processing
c. is controlled by inhibitory proteins
d. in based on posttranslational modifications
e. none of th
b
Which of the following secondary structures maybe a good DNA-binding protein?
a. zinc finger
b. leucine zipper
c. helix-turn-helix
d. all of the above
e. none of the above
d
Alterations in the DNA-histone complex that can increase or decrease transcriptional activity is termed
a. induction
b. chromatin remodeling
c. gene regulation
d. nucleosome formation
e. none of these
b
Modifications to histone tails such as acetylation by ___, allow repressed genes to become transcriptionally active. This occurs in ___ heterochromatin.
a. lysine acetyl transferases; constitutive
b. lysine acetyl transferases; facultative
c. histone deac
a
A P value in statistics is
a. a measure of the accuracy of a data set.
b. the probability of getting the observed data distribution by chance
c. arbitrarily set depending on a statistical test
d. a measure of the accuracy of a statistical test
e. none of
b
Control of transcription initiation of eukaryotic protein-coding genes involves
a. enhancers
b. promoters
c. repressors
d. activators
e. all of these
e
RNA silencing involves
a. miRNAs
b. siRNAs
c. double-stranded RNA
d. a protein called Dicer
e. all of these
e
A dihybrid cross of two heterozygotes yields 320 F2 offspring. How many are expected to resemble the homozygous recessive parental?
a. 10
b. 16
c. 20
d. 60
e. 180
c
True or False; A test cross with a heterozygous dominant individual will yield only heterozygous dominant offspring
False
True or False; Two individuals can be phenotypically identical, yet have different genotypes for a given trait
True
True or False; True-breeding individuals are produced by repeated backcrossing
True
True or False; Steroid and peptide hormone receptors are typically cytoplasmic
False
True or False; Transcriptionally active genes show lower levels of DNA methylation compared with transcriptionally inactive genes
True
True or False; Imprinting is implicated in prader-wilson and cyochondria syndromes
False
In the Hardy-Weinberg model, the ideal population is
a. very large
b. randomly mating
c. free of mutations
d. non-migrating
e. all of these
e
If the results of a chi-square test of a given set of data show a P value greater than 0.05, then the null hypothesis
a. must be rejected
b. must be accepted
c. must be rephrased
d. cannot be rejected
e. cannot be accepted
d
A and B antigens in human blood are produced by the conversion of ___ by the addition of a sugar group.
a. anti-A and anti-B antibodies
b. the H antigen
c. hemoglobin
d. anti-O antibodies
b
Familial hypercholesterolemia is a genetic disease that affects approximately one in 500 people worldwide. There is more than one genetic cause of the disease. Class I is often described as an autosomal dominant disease. Affected individuals have choleste
c
People affected by diseases caused by mtDNA defects
a. typically have cells that are heteroplamons
b. show partial penetrance
c. are sterile
d. inherited them through paternal effect
e. have epistatic respiration
a
An X-linked homozygous color-blind woman give birth to a son who is not color blind. He could have normal vision because he
a. has Down syndrome
b. has Klinefelter syndrome
c. has Turner syndrome
d. is XYY
e. has triploidy
b
Dicentric or acentric chromosomes may arise in meiosis after crossing over as a result of which kind of chromosomal mutation?
a. deletion
b. translocation
c. inversion
d. duplication
c
In familial Down syndrome resulting from Robertsonian translocation,
a. the affected individual has three copies of the complete chromosome 21.
b. the affected individual has two copies of the long arm pf chromosome 21, and one of which is attached to par
b
True or False; A gene is known to have three alleles: p, q, and r. The frequency of o is estimated at 0.70. Thus, the frequencies of q and r must be 0.15 each.
False
True or False; Down syndrome is the only human autosomal trisomy in which the individuals may survive to adulthood
False
True or False; The cause of chromosomal deletion may include radiation viral infection, chemical exposure, or transposable elements.
True
Which form of right-handed DNA is most abundantly found in nature?
a. A-DNA
b. B-DNA
c. Z-DNA
b
Down syndrome is often caused by nondisjunction. If this type of error were to occur in Meiosis II, which abnormal gamete would most likely lead to Down syndrome?
a. A gamete with two copies of chromosome 21
b. A gamete with no copies of chromosome 21
c.
a
A point at which paired chromosomes remain in contact during the first metaphase of meiosis and at which crossing over and exchange of genetic material occur between the strands is:
a. tubules
b. chromatid
c. kinetochore
d. chiasma
d
Centromeres located at the terminal end of the chromosome are known as:
a. metacentric
b. submetacentric
c. acrocentric
d. telocentric
a
Arrange the following in the proper sequence in which they occur during RNA splicing. 1. Lariat is formed 2. U2 binds to branch site adenosine 3. 3' splice site is cut
a. 1, 2, 3
b. 2, 1, 3
c. 2, 3, 1
d. 3, 2, 1
e. 3, 1, 2
b
Bacterial mRNAs are polycistronic, whereas eukaryotic mRNAs are monocistronic. Monocistronic means that:
a. Eukaryotic mRNAs contain information for one gene
b. Eukaryotic mRNAs contain information for multiple genes
c. Eukaryotic mRNAs undergo splicing
d
a
In Rho-dependent termination, which of the following is true?
a. the mRNA terminator sequence forms a hairpin loop.
b. this type only occurs in eukaryotes not prokaryotes.
c. the terminator sequence is rich in A T nucleotides.
d. the enzyme Rho unwinds th
d
Different mRNA molecules can have poly(A) tails of different lengths, from a few up 200. What do you think is a consequence of these differences? Why do you think this is?
a. Longer poly(A) tails allows the mRNA to be present for a greater time in the cel
a
Which of the following statements is not correct?
a. Prokaryotic and eukaryotic mRNAs have 5? untranslated leader sequences.
b. Only prokaryotic mRNAs are polyadenylated at their 3? ends.
c. In prokaryotes, transcription and translation are coupled.
d. Co
b
During transcription, the synthesis of the mRNA strand proceeds in which direction?
a. 5' to 3' only
b. 3' to 5' only
c. both 5' to 3' and 3' to 5'
d. either 5' to 3' or 3' to 5'
a
In eukaryotes, transcription is initiated by the formation of a pre initiation complex of transcription factors and RNA polymerase at the TATA box of the promoter. Give the correct order of the steps below.
A) the TFIID complex containing the TATA box bin
a
Which one of the following is essential for RNA polymerase to bind an E. coli promoter?
a. sigma factor
b. snRNP
c. TFIID
d. U1
a
For addition of the poly(A) tail, CPSE binds to the poly(A) consensus sequence AAUAAA which id located in the _____ of the mRNA.
a. promoter region
b. 5' UTR
c. 3' UTR
d. Protein coding region
c
Which of the following can be described as 'a sequence that can be several thousand base pairs upstream of a eukaryotic promoter and which increases gene expression as much as 200-fold.'?
a. CAAT box
b. enhancer
c. GC box
d. TATA box
b
The DNA and histone in a eukaryotic chromosome are compacted into structures called
a. proteosomes.
b. nucleosomes.
c. telomeres.
d. centromeres.
b
Which of the following statements is true concerning true genetic chimers?
a. they may be hermaphrodites.
b. they began as two sparate zygotes.
c. they are always female.
d. a and b
e. none of the above
d
What is the function of a ribosome?
a. the direct transcription
b. to attach amino acids to the appropriate tRNAs
c. to unwind the double-stranded DNA helix to enable translation
d. to hold mRNA and tRNAs in the correct positions to enable translation
e.
d
What is the basic shape of a tRNA molecule?
a. a three-dimensional cloverleaf
b. a straight strand
c. a right-hanged helix
d. a globular ball
e. a B-pleated sheet
a
What is the role of tRNA in translation?
a. it brings together two subunits of a ribosome.
b. it couples an amino acid with aminoacyl-tRNA syntheses.
c. it helps fold up the finished polypeptide chain.
it catalyzes peptide transferase activity.
d. it cata
e
This histone acts as a clamp and is not part of the optometric core:
a. H2
b. H3D
c. H1
d. H4
c
The chromosome of most prokaryotes differs from those of eukaryotes in that
a. the prokaryotic chromosome is linear, while the eukaryotic chromosome is circular
b. the prokaryotic chromosome is circular, while the eukaryotic chromosome is linear
c. the pr
b
How many polar bodies are produced during Oogenesis?
a. 1
b. 2
c. 3
d. 4
b
The single strand of mRNA that is produced during transcription has the same polarity as the ___ strand of DNA.
a. template
b. non-template
c. leading
d. lagging
e. nonsense
b
You are shadowing in a doctor's office and a patient comes in presenting with a persistent cough, unintentional weight loss, and fatigue. After further examination and questioning you find that the patient is an IV drug user and has been diagnosed with Tu
b
The DNA and histone in a eukaryotic chromosome are compacted into structures called
a. proteosomes
b. nucleosomes
c. telomeres
d. centromeres
b
In prokaryotes, the AGGAGG ribosomal binding site is located in the ___ sequence.
a. Shine-Dalgarno
b. Kozak
c. Goldberg-Hogness
d. Pribnow
a
In prokaryotes, the methionine that initiates the formation of a polypeptide chain differs from subsequently add methionine in that ___.
a. the initiating methionine that is not an amino acid
b. its tRNA anticodon is not complementary to the AUG codon
c.
d
In the Ames Test, if you observe many his+ revertants in the presence of a suspected mutagenic compound this indicates that ___.
a. the compound is most likely not mutagenic
b. the liver extract increases the potency of the suspected mutagen
c. the growth
a
The order of the structural genes on the lac operon is
a. 5'- lacZ - lazY - lacA -3'
b. 5'- lacA - lacY- lacZ -3'
c. 3'- lacZ - lacY - lacA -5'
d. 3'- lacY - lacA - lacZ -5'
a
Which of the following can be trans-dominant mutation in partial diploid cells?
a. lacZ-
b. PlacI-
c. lacIS
d. lacY-
e. lacI-
c
Net or overall probabilities are obtained by multiplying separate independent probabilities. This is formally known as
a. the sum rule
b. the chi-square test
c. the product rule
d. the sign test
e. the probability rule
c
The chemical colchicine prevents the formation of microtubules. It is commonly used in
certain experimental procedures to cause changes in cellular chromosomes. Which changes is it likely to be used to create?
a. Induction of mutant polyploid individuals
a
The distinctive fur pattern of calico cats results when genes that are responsible for the coat color are influenced by
a. age
b. X-inactivation
c. gender
d. temperature
e. other genes
c
Individuals with neurofibromatosis may have a range of phenotypes, from pigment spots on the skin to tumor like growths. This is an example of
a. incomplete penetrance
b. variable expressivity
c. age of onset
d. X-inactivation
e. gene magnification
b
A population genetic study of a certain insect revealed four alleles for the GPI (glucose-phosphate isomerase) locus. How many different genotypic classes should be found?
a. 4
b. 8
c. 10
d. 16
e. 20
c