Genetics Test 4 Homeworks

The frequency of a genetic disorder caused by a recessive allele is 0.01 in a population. What is the frequency of carriers are in the population? 1) 0.18 2) 0.24 3) 0.02 4) 0.09

1) 0.18

How many gametes are involved in the formation of dizygotic twins? 1) 4 2) 1 3) 2 4) 3

1) 4

The image below shows wild and domesticated peaches. What is this an example of? 1) Artificial selection 2) Natural selection 3) Disruptive selection 4) Stabilizing selection

1) Artificial selection

With regard to the critical checkpoints used to regulate the progression of the cell cycle, which of the following events occurs first? 1) Cyclins bind to and activate kinase enzymes. 2) Activated kinases phosphorylate target proteins. 3) Phosphorylated target proteins are used to help the cell enter the next stage of the cell cycle.

1) Cyclins bind to and activate kinase enzymes.

Eukaryotic genes often contain introns, which are not present in prokaryotes, presenting an obstacle in expressing eukaryotic genes in bacteria. How is this issue dealt with? 1) Generating cDNA from a mature mRNA 2) Methylating the intron sequences 3) Inserting the genes for the spliceosome into bacteria 4) Cutting out the introns with restriction enzymes

1) Generating cDNA from a mature mRNA

When some varieties of rice are crossed, the hybrids are viable, but subsequent generations are smaller and have less fitness. This is an example of what? 1) Hybrid breakdown 2) Hybrid sterility 3) Hybrid unviability 4) Hybrid vigor

1) Hybrid breakdown

Why is heritability of having two eyes very low? 1) Most of the variation in eye number is due to accidents and injuries 2) Eye development alleles are copy number variants not sequence mutations 3) Epistasis between eye development genes 4) No crossing over takes place in the parts of the genome that contain eye development genes

1) Most of the variation in eye number is due to accidents and injuries

Opossums can be grey or white, with the grey allele being dominate. If the frequency of the grey allele is 0.6, what frequency do you expect for white opossums? 1) 0.24 2) 0.4 3) 0.16 4) 0.48

3) 0.16

Which of the following is an example of sexual selection? 1) Peahens prefer peacocks with large and colorful tails, so those peacocks get to mate more frequently. 2) In a cold environment, rabbits with a Himalayan coat pattern can stay warm and are camouflaged against predation by owls. These rabbits survive longer, so they get to mate more. 3) Waved Albatrosses have a mating season in the Galapagos islands from December to April 4) Foxes mate for life

1) Peahens prefer peacocks with large and colorful tails, so those peacocks get to mate more frequently.

Which technique can make cDNA from RNA? 1) RT-PCR 2) zetaPCR 3) qPCR 4) Standard PCR

1) RT-PCR

The human genome is predicted to have approximately 20,000 genes while the human proteome is predicted to have approximately 290,000 proteins. Which of the following is not an explanation for why the human proteome is so much larger than the human genome? 1) Some genes are duplicated in the genome. 2) Some proteins are cleaved by a protease as a method of posttranslational modification. 3) Some genes are alternatively spliced, resulting in multiple splice variants. 4) Some mRNAs are edited, resulting in different proteins encoded by the same mRNA.

1) Some genes are duplicated in the genome.

SS individuals have normal hemoglobin and are susceptible to malaria. Ss individuals have mostly normal hemoglobin and are resist to malaria. ss individuals have sickle cell anemia. This is an example of _______. 1) Stabilizing selection 2) Disruptive selection 3) Directional selection 4) Sexual selection

1) Stabilizing selection

You attempt to insert a gene into a plasmid and transform bacteria with the result using blue-white screening. All of the resulting colonies are blue. What happened? 1) The transformation worked, but the gene insertion didn't 2) Neither the gene insertion nor the transformation worked 3) The gene insertion worked but not the transformation 4) Both the gene insertion and transformation worked

1) The transformation worked, but the gene insertion didn't

Which statement best describes an example of a cancer causing mutation in a tumor-suppressor gene? 1) a mutation that makes a cell unable to undergo programmed cell death 2) a mutation that causes cyclins to be expressed at all times 3) overexpression of a signal transduction molecule that promotes cell growth 4) a mutation that places a receptor tyrosine kinase in a continuous "on" state

1) a mutation that makes a cell unable to undergo programmed cell death

Height in a species of plant is controlled by 4 genes with additive alleles. Which of the following is a genotype you would expect for a plant of average height? 1) aaBBCcDd 2) aabbccdd 3) aabbCcDc 4) AABbCCDD

1) aaBBCcDd

Which of the following factors is typically monitored during the M checkpoint? 1) attachment of spindle fibers to kinetochores 2) the presence of DNA damage 3) cell size 4) the completion of DNA replication

1) attachment of spindle fibers to kinetochores

White clover plants produce hydrogen cyanide gas in response to herbivore insects feeding on them, deterring or even killing them. Recently white clover in urban areas was found to lack this mechanism. Its thought that since there are less herbivore insects in urban areas, the plant can save energy and resources by not producing hydrogen cyanide. This would be considered an instance of ______. 1) microevolution 2) macroevolution 3) sexual dimorphism 4) stabilizing selection

1) microevolution

What is the name of the protein that appears to regulate the entry of cells into an S phase (along with other functions)? This protein is also known as the "guardian of the genome" and is mutated in ~50% of cancers. 1) p53 2) Tumor necrosis factor 3) hexokinase 4) GCN5b

1) p53

Which type of mutation is known to accumulate in cancer cells but has no direct contribution to the cancer phenotype? 1) passenger mutations 2) alteration mutations 3) carrier mutations 4) indirect mutations

1) passenger mutations

Nutrigenomics is the study of ________. 1) the relationship between diet and the genome 2) the vitamins and minerals in the genome 3) the effect of genomics on dietary desires 4) the effect of nutrition on genome sequences

1) the relationship between diet and the genome

Calculate the standard deviation of the following values: 8, 12, 8 and 4. 1) 5.82 2) 3.26 3) 10.66 4) 14.27

2) 3.26

In snapdragons, the red and white flower alleles exhibit incomplete dominance. If the frequency of the red alleles is 0.3, what frequency of pink flowers do you expect in the population? 1) 0.21 2) 0.7 3) 0.42 4) 0.5

3) 0.42

Eye color in humans is a polygenic trait influenced by 16 genes. How many phenotypic classes of eye color would you expect? 1) 16 2) 8 3) 33 4) 64

3) 33

_______ tumors grow uncontrollably but do not metastasize.. 1) Fibrotic 2) Necrotic 3) Benign 4) Malignant

3) Benign

The PCR (polymerase chain reaction) protocol that is currently used in laboratories was facilitated by the discovery of a bacterium called Thermus aquaticus in a hot spring inside Yellowstone National Park, in Wyoming. This organism contains a heat-stable form of DNA polymerase known as Taq polymerase, which continues to function even after it has been heated to extremely high temperatures. Why would such a heat-stable polymerase be beneficial in PCR? 1) Each cycle includes a "hot" saturation phase (95°C), which allows the primers to anneal to the target DNA. 2) Each cycle includes a "hot" denaturation phase (95°C), which separates the hydrogen bonds that hold the strands of the template DNA together. 3) Each cycle includes a "hot" denaturation phase (95°C), which serves to sterilize the culture. 4) Each cycle includes a "hot" denaturation phase (95°C), which activates the Taq polymerase.

2) Each cycle includes a "hot" denaturation phase (95°C), which separates the hydrogen bonds that hold the strands of the template DNA together.

Which of the following describes an expression quantitative trait loci (eQTL)? 1) A recessive allele for an amino acid transporter has a premature stop codon that reduces the size of the protein product 2) Lactose tolerance level is determined by lactase enzyme alleles with different mutations in the promoter that influence the gene's mRNA levels 3) A dominant allele for a protein fiber has an insertion in exon 5 that causes abnormal fiber formation 4) Different hexokinase alleles have point mutations in exon 3 that influences the activity levels of the enzyme

2) Lactose tolerance level is determined by lactase enzyme alleles with different mutations in the promoter that influence the gene's mRNA levels

Which of the following is not true about bisulfite sequencing? 1) It cannot detect histone methylation 2) Methylated cytosines are removed an replaced with artificial bases 3) Non-methylated cytosines appear as thymines in the sequencing data 4) Methylated cytosine bases are protected from conversion to uracil

2) Methylated cytosines are removed an replaced with artificial bases

During what stage of the cell cycle is DNA replicated? 1) G2 2) S 3) G1 4) M

2) S

Female spiders are usually significantly larger than male spiders. This phenomena is called _________. 1) Sexual selection 2) Sexual dimorphism 3) Disruptive selection 4) Genetic drift

2) Sexual dimorphism

What is a cDNA molecule? 1) DNA sequences that are highly conserved among all organisms 2) a DNA copy of an RNA molecule produced by reverse transcription 3) a molecule rich in restriction cut sites 4) copies of introns with exons excluded

2) a DNA copy of an RNA molecule produced by reverse transcription

Cancer is: 1) an inherited disease caused by a single mutation in an oncogene. 2) a genetic disease caused by an accumulation of mutations in somatic cells. 3) a genetic disease caused by a single mutation in p53 tumor suppressor. 4) a genetic disease in which the same core genes are mutated in all cancers.

2) a genetic disease caused by an accumulation of mutations in somatic cells

How does one target specific DNA sequences of the template to be amplified by polymerase chain reaction? 1) by designing probes complementary to regions on both sides of the specific target 2) by designing primers complementary to regions on both sides of the specific target 3) cutting areas on both sides of the target sequence with the same restriction enzyme 4) including ddNTPs in the PCR reaction

2) by designing primers complementary to regions on both sides of the specific target

When sequencing a genome, coverage is the: 1) number of reference sequences available for a species. 2) number of times a particular base is found in the same location in multiple reads of a sequence. 3) percent of the genome that is sequenced at least one time. 4) percent of variation that is thought to be covered by sequencing data for a species.

2) number of times a particular base is found in the same location in multiple reads of a sequence.

In which of the following biochemical reactions is it common to use ddNTPs (dideoxyribonucleoside triphosphates)? 1) transfection 2) sanger sequencing 3) restriction digestion 4) immunoprecipitation

2) sanger sequencing

Bioinformatics includes all of the following except _______. 1) using mathematical tools to make sense of biological systems. 2) using enzymes to combine DNA from two different sources in a test tube. 3) developing computer-based tools for genome analysis. 4) using computer programs to align DNA sequences.

2) using enzymes to combine DNA from two different sources in a test tube.

A population of fish has and variety of body colors and patterns. After an oil spill, only white fish with red stripes remain. What is this an example of? 1) Founder effect 2) Cladogenesis 3) Bottleneck effect 4) Artificial selection

3) Bottleneck effect

All of these are known to cause cancer EXCEPT ________. 1) Some viruses 2) Chronic infections 3) DNA repair 4) Radiation

3) DNA Repair

How are restriction fragments put together? 1) Chemical catalysts 2) Methylating the ends so they stick together 3) DNA ligase 4) DNA polymerase

3) DNA ligase

A species of beetles have different horn shapes. A group of two-pronged horn beetles are in log that floats to a remote island. A population of beetles form on the island and they all have two-pronged horns. What is this an example of? 1) Anagenesis 2) Bottleneck effect 3) Founder effect 4) Stabilizing selection

3) Founder effect

Which of the following is an example of G x E interaction? 1) The pink color of flamingos is totally dependent on their diet 2) Over 10,000 alleles influence height in humans 3) Lobsters with allele A grow larger than lobsters with allele a in cold water environments. In warm tropical waters lobsters with allele a grow larger. 4) Variety 1 of a crop always has a greater yield than variety 2

3) Lobsters with allele A grow larger than lobsters with allele a in cold water environments. In warm tropical waters lobsters with allele a grow larger.

Which technique would be used to sequence the amino acids in a protein? 1) Microarray 2) Shotgun sequencing 3) Mass specrometry 4) X-ray crystallography

3) Mass spectrometry

In general, mutations in genes that code for cell-adhesion molecules, cytoskeleton regulators, and proteolytic enzymes lead to which feature of malignant cancer cells? 1) Inhibition of apoptosis 2) Uncontrolled cell division 3) Metastasis 4) Inhibition of DNA repair

3) Metastasis

How are restriction sites typically added to the ends of a gene? 1) Making the gene with artificial chemical synthesis 2) Ligation of restriction site DNA to the ends of the gene fragment 3) PCR with primers containing restriction sites 4) Site directed mutatgenesis

3) PCR with primers containing restriction sites

Why isn't DNA polymerase I not needed for PCR? 1) There isn't a lagging strand 2) The primers are premade 3) The primers are made of DNA 4) Heat separates the DNA strands

3) The primers are made of DNA

How do heat shock and electroporation allow for transformation of bacteria? 1) These techniques induce gene expression changes in the bacteria, making it more receptive to foreign DNA 2) These techniques cause the bacteria to form sex pili that take up foreign DNA 3) These techniques destabilize the bacterial membrane, causing pores to open that foreign DNA can pass through. 4) These techniques deplete the bacteria's genome, forcing it to take up foreign DNA

3) These techniques destabilize the bacterial membrane, causing pores to open that foreign DNA can pass through.

Which of the following is an example of behavioral isolation? 1) Two groups of birds don't mate because of differing plumage colors 2) Two groups of beetles have incompatible sex organs 3) Two groups of jumping spider don't mate because of differences in their courtship dances 4) Two groups of frogs don't mate because one lives in ponds and other lives in streams

3) Two groups of jumping spider don't mate because of differences in their courtship dances

Any agent that causes damage to DNA is a potential ________. 1) oncogene 2) proto-oncogene 3) carcinogen 4) pollutant

3) carcinogen

Using modern techniques of sequencing by synthesis and the shotgun approach, sequences are assembled into contigs by ________. 1) placing them on previously generated genetic maps 2) cloning them into plasmid vectors 3) computer analysis looking for sequence overlaps 4) treatment with DNA ligase

3) computer analysis looking for sequence overlaps

One major difference between prokaryotic and eukaryotic genes is that eukaryotic genes can contain internal sequences, called ________, which get removed in the mature message. 1) exons 2) enhancers 3) introns 4) promoters

3) introns

What type of gene encodes products that normally promote appropriate cell growth and division? 1) transgene 2) tumor suppressor gene 3) proto-oncogene 4) pseudogene

3) proto-oncogene

Restriction endonucleases are especially useful if they generate "sticky" ends. What makes an end sticky? 1) 5' cap 2) blunt ends 3) single-stranded complementary sequence 4) poly-A sequences

3) single-stranded complementary sequence

Expression vectors differ from cloning vectors by ________. 1) a reduced number of cloning sites 2) the presence of a selectable marker gene 3) the presence of necessary sequences to initiate transcription and translation (promoter, terminator, etc.) 4) the ability to be introduced into host cells

3) the presence of necessary sequences to initiate transcription and translation (promoter, terminator, etc.)

What is an open reading frame (ORF)? 1) Any gene sequence that is transcribed into an RNA 2) An mRNA that codes for a protein 3) A nucleotide sequence of a gene including introns and gene regulatory regions 4) A nucleotide sequence that is translated into a protein

4) A nucleotide sequence that is translated into a protein

Which of the following is used to calculate Narrow-sense heritability? 1) Environmental variance 2) Interactive variance 3) Dominance variance 4) Additive variance

4) Additive variance

In a species of Galapagos finch, thick beaked individuals excel at cracking nuts, while thin beaked individuals excel at picking out grubs from trees. Individuals with intermediate beaks aren't good at either task. This is an example of what? 1) Stabilizing selection 2) Directional selection 3) Sexual selection 4) Disruptive selection

4) Disruptive selection

The sequencing of the human genome led to the realization that chromosome 19 contains many genes while chromosomes 13 and Y contain relatively few. What does this finding imply about the density of genes in a genome? 1) Genes are uniformly distributed throughout the genome. 2) Genes are uniformly distributed on chromosomes but not through the entire genome. 3) Genes have no organization and randomly appear throughout the genome and chromosomes. 4) Genes are not uniformly distributed and appear in clusters separated by gene deserts.

4) Genes are not uniformly distributed and appear in clusters separated by gene deserts.

Which is the correct order of experiments for creating recombinant bacteria? I. Use PCR to amplify a gene of interest. II. Transform bacteria with the plasmid III. Perform a ligation reaction with the gene of interest and the plasmid. IV. Digest the gene of interest and a plasmid with restriction enzymes. 1) I -> III -> II -> IV 2) IV -> III -> I -> II 3) I -> II -> III -> IV 4) I -> IV -> III - > II

4) I -> IV -> III - > II

The Philadelphia chromosome is a translocation between chromosomes 22 and 9 that leads to translation of a BCR-ABL fusion protein. The normal ABL gene is a proto-oncogene that codes for a kinase involved in a cell signaling pathway. How does this chromosome abnormality lead to cancer? 1) The fusion protein causes mutations that lead to cancer. 2) In the fusion protein, the ABL protein is non-functional. 3) The abnormal chromosomes cannot line up in mitosis and cells cannot undergo normal cell division. 4) In the fusion protein, the ABL protein is always active.`

4) In the fusion protein, the ABL protein is always active.

A new gene is discovered during the sequencing of a bacterial genome. After a BLAST analysis, the new gene aligns with a known sequence from the same bacterium. The sequence identity is 95%. Which of the following statements best describes the relationship of the newly discovered gene and the known gene? 1) It is an ortholog to the known gene and is a result of an older gene duplication. 2) It is a paralog to the known gene and is a result of an older gene duplication. 3) It is an ortholog to the known gene and is a result of a recent gene duplication. 4) It is a paralog to the known gene and is a result of a recent gene duplication.

4) It is a paralog to the known gene and is a result of a recent gene duplication.

All of the following are checkpoints in the cell cycle EXCEPT ________. 1) M 2) G2/M 3) G1/S 4) M/G1

4) M/G1

You find the heritability of height of in a population water oak trees in upstate South Carolina to be 0.67. Your colleague finds the heritability of height of in a population water oak trees in south Alabama to be 0.44. How is this possible? 1) There must be an error - heritability is the same fixed value for all members of species 2) One population must have been exposed to mutagens 3) The two populations must be different subspecies of water oak 4) Measured heritability depends on environmental variation present in population being studied

4) Measured heritability depends on environmental variation present in population being studied

You are studying the Virginia opossum, Didelphis virginiana. You find 11 genes that influence the weight of newborn joeys, and that the mother's diet also influences birth weight. What term best describes this trait? 1) Polygenic 2) Qualitative 3) Monogenic 4) Multifactorial

4) Multifactorial

Which of the following is NOT a major point of the multiple-gene hypothesis? 1) Two or more loci show an additive effect on the expression of phenotype (polygenic inheritance). 2) Additive alleles contribute to a single quantitative trait to produce substantial phenotypic variation. 3) Each gene loci is occupied by either additive or nonadditive allele. 4) Phenotypic traits show discontinuous variation and can be cannot be quantified, only qualified

4) Phenotypic traits show discontinuous variation and can be cannot be quantified, only qualified

What is the difference between standard deviation and standard error? 1) Standard error is only used for genetic data, other fields use standard deviation 2) Standard deviation uses the mean, standard error uses the median 3) Standard error leaves out outliers 4) Standard error takes sample size into account

4) Standard error takes sample size into account

Aligning genome sequences from different organisms to study gene and genome evolution is referred to as ________. 1) metagenomics 2) evogenomics 3) stone-age genomics 4) comparative genomics

4) comparative genomics

Which of the following correctly lists the processes in order for one cycle of polymerase chain reaction (PCR)? 1) denature DNA; add fresh enzyme; anneal primers; add dNTPs; extend primers 2) anneal primers; denature DNA; extend primers 3) extend primers; anneal primers; denature DNA 4) denature DNA; anneal primers; extend primers

4) denature DNA; anneal primers; extend primers

A genetic bottleneck 12,000 years ago led to ______ in cheetahs, causing deleterious recessive alleles to become much more common 1) disruptive selection 2) sexual dimorphism 3) artificial selection 4) inbreeding

4) inbreeding

You are studying corn and find that higher stalk height is correlated with larger cob size. Which of the following r values would be expected for this relationship? 1) r = -0.78 2) r = +0.31 3) r = -0.31 4) r = +0.78

4) r = +0.78