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You are studying a sample of 10 mice with the following genotypes: four mice are D/d, two mice are D/d, and four mice are d/d. In this scenario, what is the frequency of the d allele?

0.5

A botanist has determined that flower color in a new species of orchid is determined by a gene with two alleles, one of which is dominant. The dominant flower color is red. How many dominant alleles must an orchid possess in order to demonstrate red flowers?

1

Hemophilia is an X-linked recessive trait. A woman with hemophilia and a man without hemophilia already have a son. What are the chances that the son will have hemophilia?

100%

Drosophila eyes are normally red. Several purple-eyed strains have been isolated as spontaneous mutants, and the purple phenotype has been shown to be inherited as a Mendelian autosomal recessive in each case. To investigate allelism between these different purple mutations, two purple-eyed pure strains were crossed. If the purple mutations are in different genes (i.e., they are not allelic), the phenotypic ratios in the F1are expected to be:

100% red.

Which of the following statements regarding the development of cancer is true?

Cancer cells exhibit abnormal cell growth and will invade other host tissues.

Deducing the protein encoding genes from genomic sequences involves:ORF detection.direct evidence from cDNA sequences.predictions of binding site.predictions based on codon bias.

All of the answer options are correct.

Deducing the protein encoding genes from genomic sequences involves

All of the answer options are correct. (ORF detection. , direct evidence from cDNA sequences , predictions of binding site. , predictions based on codon bias.)

A scientist is culturing bacteria in media containing lactose, but no glucose. Which of the following statements is likely true of these cells?

All of these

A plasmid vector has a gene for erythromycin resistance (EryR) and a gene for ampicillin resistance (AmpR). The Amp gene is cut with restriction enzyme, and donor DNA treated with the same enzyme is added. What genotype of cells needs to be selected to show evidence of transformation?

AmpSEryR

Imagine that the pedigree here depicts inheritance of a simple single-gene disease in a family. What can you infer about the disease depicted? [female parent gets it, then 1 out of 4 kids, a male, gets it]

Autosomal (not on X-chromosome) recessive

Fruit flies can have a mutant trait for complete black- or ebony-colored bodies compared to the black-and-tan-striped wild type. When purebred ebony flies are crossed with purebred wild-type flies, 747 wild-type and 253 ebony flies are generated. What type of genetic pattern does the ebony mutant display?

Autosomal recessive

Mice that are homozygous for a complete deletion of the wild-type gene "T" develop multiple tumors in a variety of tissues very early in life. Gene "T" is most likely:

a tumor suppressor gene.

The grasses (such as barley, rice, sorghum, and corn) vary widely in the size of their genomes, yet they are descended from a common ancestor. What accounts for the variation in DNA content (i.e., the total amount of DNA)?

accumulation of LTR retrotransposons

In the eukaryotic GAL system, the physiologically regulated step is

activity of the activation-domain of the transcriptional regulator

A researcher is studying a pedigree of a family afflicted by an unknown disease. He notices that every generation depicted in the pedigree demonstrates at least one afflicted individual. Furthermore, both males and females in the pedigree can demonstrate this disease, and both sexes can pass this disease to progeny (either daughters or sons). The researcher is most likely studying a(n)

autosomal dominant disorder.

Which of the following is NOT true of a cDNA clone? A) cDNAs are generally copies of mRNA from expressed genes. B) Reverse transcriptase activity is required for cDNA cloning. C) cDNA clones lack exons, as introns are spliced together before cloning. D) cDNAs are typically smaller than the chromosomal sequence for a particular gene. E) cDNAs can be fused to a promoter to enable expression of the encoded gene.

cDNA clones lack exons, as introns are spliced together before cloning. (They lack INTRONS, not exons!)

The repression of the transcription of lactose-metabolizing genes in the presence of glucose is an example of:

catabolite repression

Sanger DNA sequencing determines the nucleotide sequence because:

dideoxy nucleotides terminate the growing DNA strand.

In the 1940s, George Beadle and Edward Tatum developed the one-gene-one-polypeptide hypothesis by mutating the genes of Neurospora crassa (bread mold). They identified mutants that were unable to synthesize amino acids, such as arginine. When multiple mutant strains were identified for a single trait (adenine synthesis deficient), they showed that:

each step in the biochemical pathway was mediated by an enzyme encoded by a single gene.

Eukaryotic and bacterial RNA polymerases are different such that:

eukaryotes have several types of RNA polymerases, one of which can synthesize mRNA and also coordinate mRNA processing, whereas bacteria only have one type of RNA polymerase that does not coordinate mRNA processing.

A partial diploid of genotype I+ P+ O+ Z+ Y- / I+ P- O+ Z+ Y+ will show:

inducible production of b-galactosidase and permease

The class of genes required for establishing the anteroposterior axis is:

maternal-effect genes

The class of genes required for establishing the anteroposterior axis is the:

maternal-effect genes.

The following mechanism/factor has impacts to the molecular processes that lead to epigenetic changes, except ________.

mutation of the genes

The fluctuation test of Luria and Delbruck showed that:

mutations can arise spontaneously before exposure to the selecting agent.

A linear DNA molecule has n target sites for restriction enzyme EcoRI. How many fragments will be produced after complete digestion?

n + 1

A corn plant is homozygous for a mutant allele that results in no pigment in the seed (i.e., white). The mutant is caused by Ds insertion that often exits late in seed development, when there is an active Ac element in the genome. If there is NO active Ac element, the seeds of this plant will be:

no pigment (i.e., white)

A partial diploid of genotype I^S P+ O+ Z+ / I+ P+ O+ Z- will show:

no production of b-galactosidase

A mutation does not affect the length of a gene but results in an abnormally short protein. The mutation is most likely of a type called:

nonsense

In D. melanogaster, when P cytotype (lab stock) females are crossed to M cytotype (wild) males, the resulting F1 progeny are:

normal.

In homeotic mutants:

one body structure has been changed into another.

Genes that have been inherited from a common ancestor are called

orthologs

Genes that are related by gene-duplication events within the same genome are called

paralogs

You used ionizing radiation to mutagenize Chlamydomonas, a single-cell photosynthetic eukaryote that normally swims by means of two flagella. You screen the mutagenized population for members who lack flagella, and through this screen identify a mutation in a specific gene. When you further examine these mutants, you notice that they do not demonstrate any RNA or protein products from the gene you are studying (i.e., no shortened protein, no protein with aberrant amino acids, etc.). The type of mutation you most likely introduced is a

regulatory-region mutation.

In the presence of the repressor molecule and free tryptophan, the trp operon is:

repressed

An autonomous element:

requires no other elements for its mobility.

The Ames test is used for determining whether a particular chemical acts as a mutagen. It does this by selecting for:

revertants of His- mutations in Salmonella typhimurium

Under conditions where tryptophan is scarce:

the attenuator stem-loop structure forms, allowing transcription to continue

Introns begin and end with...

GU (begin) and Ag (end)

Klinefelter males (XXY) have a single Barr body, indicating one X has been subject to X chromosome inactivation. What is the most likely explanation for the observation that these males are not completely normal?

Gene dosage early in embryogenesis, prior to X chromosome inactivation, is critical for proper development.

Which of the following diseases is/are LEAST likely to be caused by excessive exposure to UV light?

Huntington disease

A population is reproductively isolated. Which of the following is primarily responsible for the introduction of new alleles into this population?

Mutations in the germ line

How do epigenetic traits differ from traditional genetic traits, such as the differences in color and shape of peas that Mendel studied?

New phenotype is caused by modifications to chromatin

Does the RNAi decay mechanism involve transgenes?

No

A partial diploid of genotype I^S P+ O+ Z+ / I+ P+ O+ Z- will show:

No production of b-galactosidase

A scientist studying attenuation of the tryptophan operon would find which result when there is an abundance of tryptophan?

Transcription will terminate when segments 3 and 4 of the leader mRNA base pair with each other.

The following are key questions concerning the number, identity, and function of genes taking part in development, except ________.

Which genes are important to determine the eye color for the organism?

In the human pedigree shown below, black symbols indicate individuals suffering from a rare genetic disease, whereas white symbols represent people who do not have the disease.Based on the pedigree, what is the most likely mode of inheritance of this rare genetic disease?

X-linked dominant

Epigenetics has been described as "inheritance, but not as we know it." Do you think this is a good definition of epigenetics?

Yes, because epigenetic phenotypes are inherited, but they do not strictly follow Mendelian rules of inheritance.

Epigenetics has been described as "inheritance, but not as we know it." Is this a good definition of epigenetics? Why or why not?

Yes, because epigenetic phenotypes are inherited, but they do not strictly follow Mendelian rules of inheritance.

The strategy for obtaining a genomic sequence can be divided into four steps: 1) overlap contigs for complete sequence, 2) sequence each fragment, 3) cut many genome copies in to random fragments, and 4) overlap sequence reads. What is the order of the four steps?

3, 2, 4, 1 (cut many genome copies in to random fragments, sequence each individual fragment, overlap sequence reads of fragments, overlap contigs to obtain the complete sequence)

The strategy for obtaining a genomic sequence can be divided into four steps: 1) overlap contigs for complete sequence, 2) sequence each fragment, 3) cut many genome copies into random fragments, and 4) overlap sequence reads. What is the order of the four steps?

3, 2, 4, and 1

The red fox has 17 pairs of large, long chromosomes. The arctic fox has 26 pairs of smaller chromosomes. What do you expect to be the chromosome number in somatic tissues of a red fox/arctic fox hybrid?

43

If a plant of genotype A/a is selfed, and numerous offspring are scored, what proportion of the progeny is expected to have homozygous genotypes?

50%

In sweet peas, the synthesis of purple anthocyanin pigment in the petals is controlled by two genes, B and D. The pathway is [pic]. The Plant 1 and plant 2 are pure breeding in both gene B and gene D. Plant 1 is unable to catalyze the first reaction, due to the mutation of gene B and produces white color petals. Plant 2 is unable to catalyze the second reaction, due to the mutation of gene D and produces blue color petals. Wild type B allele is dominant to mutant allele b. Wild type D allele is dominant to mutant allele d. F1 progeny are produced from the crossing between plant 1 and plant 2. If two F1 progeny were self-crossed, F2 progeny are produced. What ratio of purple: blue: white plants would you expect in the F2?

9:3:4

The amount of milk produced per day by a cow is an example of a:

Continuous trait.

You are studying a highly inbred strain of barley. After many generations of inbreeding, you now assume that the genetic variation is zero. Suppose that you raise many individuals of your barley strain in a field in southeastern Michigan and then measure their height after one month of growth. You find that the variance in their height is 4.0. The broad-sense heritability of this trait is 0. From this particular study you can conclude that:

If you were to repeat the same experiment in Iowa, you would obtain the same broad-sense heritability

The CRISPR-Cas9 system in bacteria is akin to our body's

Immune system

A quantitative geneticist measures the broad-sense heritability for bill length in an isolated population of ducks to be 0.75. This result suggests that:

In the population tested, 75% of the variance in bill length is due to genetic differences among individuals

A partial diploid of genotype I- P+ O+ Z+ / I+ P+ O+ Z- will show:

Inducible production of b-galactosidase

Which of the following would NOT be considered a key feature of paramutation?

Inheritance of the traits exhibits classic Mendelian phenotypic ratios.

Which of the following are characteristics of an E. coli strain of genotype F- gal+ lac- pur+ ile- strR?

It is auxotrophic for lactose.

In humans, males have only one X chromosome and females have two, yet housekeeping X chromosome genes are expressed in roughly equal amounts in males and females. How can this be explained?

One X chromosome in females is inactivated

Which of the following statements is/are TRUE about reverse genetics?

Reverse genetics analysis starts with a known DNA sequence, mRNA, or protein, and it can be performed by random mutagenesis, targeted mutagenesis, or by phenocopying.

Which of the following diseases is/are MOST likely to be caused by excessive exposure to UV light?

Skin cancer

What is meant by "codon bias"?

Some organisms will use specific codons for amino acids they specify

In recent years, techniques have been developed to clone mammals through a process called nuclear transfer. Research has demonstrated that when a nucleus from a differentiated somatic cell is transferred to an egg cell only a small percent of the resulting embryos complete development and many of those that do die shortly after birth. In contrast, when a nucleus from an undifferentiated embryonic stem cell is transferred into an egg cell, the percentage of embryos that complete development is significantly higher. Propose a possible reason for why successful development of cloned embryos is higher when the nucleus transferred comes from an undifferentiated embryonic stem cell.

The gene expression program of cells is regulated by epigenetic mechanisms, and the epigenetic pattern of stem cells is very different from the pattern of a differentiated somatic cell.

What role does the guide RNA play in the gene-editing CRISPR-Cas 9 system?

The guide RNA binds to the target DNA and directs the Cas9 nuclease activity.

What structural feature of DNA suggests a possible method of its replication?

The nucleotides between nucleotide strands are complementarily paired.

What would be required to prove that a phenotype is caused by an epigenetic change?

The phenotype must be heritable with modified chromatin and an unaltered nucleotide sequence.

In the following pedigree, the shaded symbols represent a rare X-linked disease of the blood. The propositus has 45 chromosomes and is sterile. Propose a single mechanism to account for the sterility and the blood disease in this female.

The woman is likely demonstrating a case of Turner syndrome.

An Hfr microbial strain would best be described as:

a bacterium containing a chromosomally integrated plasmid conferring mating competency.

A pure line of plants of genotype a/a; b/b; c/c; d/d; e/e (all recessive wild type) was crossed to a wild type. One F1 individual expresses the recessive alleles d and e. This individual arose most likely from:

a deletion in the wild-type parent

The most closely related genes either within a single organism or between two different organisms are called

homologs

The most closely related genes either within a single organism or between two different organisms are called:

homologs

A corn plant is homozygous for a mutant allele that results in no pigment in the seed (i.e., white). The mutant is caused by Ds insertion that often exits late in seed development, when there is an active Ac element in the genome. If there is active Ac element, the seeds of this plant will be:

pigmented all over.

On a fox ranch in Wisconsin, a mutation arose that gave a "platinum" coat color. The platinum color proved very popular with buyers of fox coats, but the breeders could not develop a pure-breeding platinum strain. Every time two platinums were crossed, some normal foxes appeared in the progeny. For example, the repeated matings of the same pair of platinums produced 82 platinum and 38 normal progeny. All other such matings gave similar progeny ratios. State a concise and correct genetic hypothesis that accounts for these results.

platinum coat color alleles in the homozygous state is lethal in foxes.

In a classical genetic experiment, Newcombe spread E. coli cells on complete medium. After several generations of growth, he replica-plated the colonies onto two plates with complete medium plus a selective agent. Colonies on the first replica were left untouched, while on the second replica, they were respread, slowing bacteria from each colony to be "moved" to a new location on the plate. Significantly more mutants after spreading (resistant to the selective agent) were ob served than if they had not been respread. The experiment was used to:

provide evidence that mutations occur in the absence of the selective agent.

An enhancer is best described as a:

regulatory sequence in DNA that acts to promote the expression of specific eukaryotic genes

What is the mechanism that ensures Mendel's first law of segregation?

segregation of homologous chromosomes during meiosis I

The two types of bacterial transposons are

simple and composite transposons

Retrotransposons move via an intermediate that is:

single stranded RNA

Chargaff's rules do NOT hold for which of the following genome types?

single-stranded DNA virus

A mutation that occurred in a plant petal would be best termed:

somatic.

Glutamine is encoded by CAA and CAG codons. If a normal CAA codon is mutated to CAC, the codon will produce histidine instead of glutamine. This is a _____ mutation.

transversion and missense

A transversion somewhere with gene "B" in a laboratory plant results in the production of a mutant mRNA that is much longer than the wild type. This transversion is most likely located:

within a splice site of gene "B"