Chapter 19 and 20 AP Bio

Expression of a cloned eukaryotic gene in a bacterial cell involves many challenges. The use of mRNA and reverse transcriptase is part of a strategy to solve the problem of A) post-transcriptional processing. B) electroporation. C) post-translational processing. D) nucleic acid hybridization. E) restriction fragment ligation.

A) post-transcriptional processing

20) Antiviral drugs that have become useful are usually associated with which of the following properties? A) ability to remove all viruses from the infected host B) interference with viral replication C) prevention of the host from becoming infected D) removal of viral proteins E) removal of viral mRNAs

B) interference with viral replication

Why are yeast cells frequently used as hosts for cloning? A) They easily form colonies. B) They can remove exons from mRNA. C) They do not have plasmids. D) They are eukaryotic cells. E) Only yeast cells allow the gene to be cloned.

D) they are eukaryotic cells

12) Which viruses have single-stranded RNA that acts as a template for DNA synthesis? A) lytic phages B) proviruses C) viroids D) bacteriophages E) retroviruses

E) retroviruses

Which of the following is used to make complementary DNA (cDNA) from RNA? A) restriction enzymes B) gene cloning C) DNA ligase D) gel electrophoresis E) reverse transcriptase

E) reverse transcriptase

CML (chronic myelogenous leukemia) results from a translocation between human chromosomes 9 and 22. The resulting chromosome 22 is significantly shorter than usual, and it is known as a Philadelphia (Ph') chromosome. The junction at the site of the translocation causes overexpression of a thymine kinase receptor. A new drug (Gleevec or imatinib) has been found to inhibit the disease if the patient is treated early. One possible use of transgenic plants is in the production of human proteins, such as vaccines. Which of the following is a possible hindrance that must be overcome? A) prevention of transmission of plant allergens to the vaccine recipients B) prevention of vaccine-containing plants being consumed by insects C) use of plant cells to translate non-plant-derived mRNA D) inability of the human digestive system to accept plant-derived protein E) the need to cook all such plants before consuming them

A) prevention of transmission of plant allergens to the vaccine recipients

A eukaryotic gene has "sticky ends" produced by the restriction endonuclease EcoRI. The gene is added to a mixture containing EcoRI and a bacterial plasmid that carries two genes conferring resistance to ampicillin and tetracycline. The plasmid has one recognition site for EcoRI located in the tetracycline resistance gene. This mixture is incubated for several hours, exposed to DNA ligase, and then added to bacteria growing in nutrient broth. The bacteria are allowed to grow overnight and are streaked on a plate using a technique that produces isolated colonies that are clones of the original. Samples of these colonies are then grown in four different media: nutrient broth plus ampicillin, nutrient broth plus tetracycline, nutrient broth plus ampicillin and tetracycline, and nutrient broth without antibiotics. Bacteria that do not take up any plasmids would grow on which media? A) the nutrient broth only B) the nutrient broth and the tetracycline broth C) the nutrient broth and the ampicillin broth D) the tetracycline broth and the ampicillin broth E) all three broths

A) the nutrient broth only

Which of the following would not be true of cDNA produced using human brain tissue as the starting material? A) It could be amplified by the polymerase chain reaction. B) It could be used to create a complete genomic library. C) It was produced from mRNA using reverse transcriptase. D) It could be used as a probe to detect genes expressed in the brain. E) It lacks the introns of the human genes.

B) It could be used to create a complete genomic library.

Which of the following statements is consistent with the results? *image 5 A) B is the child of A and C. B) C is the child of A and B. C) D is the child of B and C. D) A is the child of B and C. E) A is the child of C and D.

B) C is the child of A and B.

Which of the following tools of recombinant DNA technology is incorrectly paired with its use? A) restriction enzyme -- analysis of RFLPs B) DNA ligase -- cutting DNA, creating sticky ends of restriction fragments C) DNA polymerase -- polymerase chain reaction to amplify sections of DNA D) reverse transcriptase -- production of cDNA from mRNA E) electrophoresis -- separation of DNA fragments

B) DNA ligase -- cutting DNA, creating sticky ends of restriction fragments

13) What is the function of reverse transcriptase in retroviruses? A) It hydrolyzes the host cell's DNA. B) It uses viral RNA as a template for DNA synthesis. C) It converts host cell RNA into viral DNA. D) It translates viral RNA into proteins. E) It uses viral RNA as a template for making complementary RNA strands.

B) It uses viral RNA as a template for DNA synthesis.

Analysis of the data obtained shows that two students each have two fragments, two students each have three fragments, and two students each have one only. What does this demonstrate? A) Each pair of students has a different gene for this function. B) The two students who have two fragments have one restriction site in this region. C) The two students who have two fragments have two restriction sites within this gene. D) The students with three fragments are said to have "fragile sites." E) Each of these students is heterozygous for this gene.

B) The two students who have two fragments have one restriction site in this region.

Pharmacogenetics is an increasingly important discipline that uses genetic information to tailor the prescription of drug treatments to individuals. In the case of chemotherapy for breast cancer, for example, different patients need and/or respond to different treatments. Breast tumor biopsy specimens can be typed for a number of gene expression patterns. Together, these can provide risk analysis for the likely aggressive growth and metastasis of the tumor. How can this most help the physician and patient? A) Some patients want to know as much as possible. B) This can help them to decide whether and what kind of chemotherapy is warranted. C) This can help them decide whether the tumor should be removed. D) Some physicians may use the information to decide what to do, but not tell the patient. E) This can help to aggregate health statistics.

B) This can help them to decide whether and what kind of chemotherapy is warranted.

14) Which of the following can be effective in preventing the onset of viral infection in humans? A) taking vitamins B) getting vaccinated C) taking antibiotics D) applying antiseptics E) taking nucleoside analogs that inhibit transcription

B) getting vaccinated

A paleontologist has recovered a bit of tissue from the 400-year-old preserved skin of an extinct dodo (a bird). To compare a specific region of the DNA from the sample with DNA from living birds, which of the following would be most useful for increasing the amount of dodo DNA available for testing? A) RFLP analysis B) polymerase chain reaction (PCR) C) electroporation D) gel electrophoresis E) Southern blotting

B) polymerase chain reaction (PCR)

Which of the following sequences in double-stranded DNA is most likely to be recognized as a cutting site for a restriction enzyme? A) AAGG TTCC B) AGTC TCAG C) GGCC CCGG D) ACCA TGGT E) AAAA TTTT

C) GGCC CCGG

Plants are more readily manipulated by genetic engineering than are animals because A) plant genes do not contain introns. B) more vectors are available for transferring recombinant DNA into plant cells. C) a somatic plant cell can often give rise to a complete plant. D) genes can be inserted into plant cells by microinjection. E) plant cells have larger nuclei.

C) a somatic plant cell can often give rise to a complete plant.

A group of six students has taken samples of their own cheek cells, purified the DNA, and used a restriction enzyme known to cut at zero, one, or two sites in a particular gene of interest. Their next two steps, in order, should be A) use of a fluorescent probe for the gene sequence, then electrophoresis. B) electrophoresis of the fragments followed by autoradiography. C) electrophoresis of the fragments, followed by the use of a probe. D) use of a ligase that will anneal the pieces, followed by Southern blotting. E) use of reverse transcriptase to make cDNA, followed by electrophoresis.

C) electrophoresis of the fragments, followed by the use of a probe.

25) In the figure, at the arrow marked II, what enzyme(s) are being utilized? *image 2 A) reverse transcriptase B) viral DNA polymerase C) host cell DNA polymerase D) host cell RNA polymerase E) host cell DNA and RNA polymerases

C) host cell DNA polymerase

DNA technology has many medical applications. Which of the following is not done routinely at present? A) production of hormones for treating diabetes and dwarfism B) production of microbes that can metabolize toxins C) introduction of genetically engineered genes into human gametes D) prenatal identification of genetic disease alleles E) genetic testing for carriers of harmful alleles

C) introduction of genetically engineered genes into human gametes

Pharmacogenetics is an increasingly important discipline that uses genetic information to tailor the prescription of drug treatments to individuals. In the case of chemotherapy for breast cancer, for example, different patients need and/or respond to different treatments. Patients whose tumors are HER-2 positive respond to herceptin whereas other patients do not. Patients whose tumors have estrogen receptors will be best served if A) their estrogen receptors are blocked by using RNAi. B) their estrogen release is activated and/or elevated. C) the estrogen receptors are blocked by other molecules that can use the same receptors. D) they are given herceptin as well as estrogen. E) they are given a complete hysterectomy.

C) the estrogen receptors are blocked by other molecules that can use the same receptors.

A group of six students has taken samples of their own cheek cells, purified the DNA, and used a restriction enzyme known to cut at zero, one, or two sites in a particular gene of interest. Why might they be conducting such an experiment? A) to find the location of this gene in the human genome B) to prepare to isolate the chromosome on which the gene of interest is found C) to find which of the students has which alleles D) to collect population data that can be used to assess natural selection E) to collect population data that can be used to study genetic drift

C) to find which of the students has which alleles

7) Which of the following is characteristic of the lytic cycle? A) Many bacterial cells containing viral DNA are produced. B) Viral DNA is incorporated into the host genome. C) The viral genome replicates without destroying the host. D) A large number of phages are released at a time. E) The virus-host relationship usually lasts for generations.

D) A large number of phages are released at a time.

CML (chronic myelogenous leukemia) results from a translocation between human chromosomes 9 and 22. The resulting chromosome 22 is significantly shorter than usual, and it is known as a Philadelphia (Ph') chromosome. The junction at the site of the translocation causes overexpression of a thymine kinase receptor. A new drug (Gleevec or imatinib) has been found to inhibit the disease if the patient is treated early. Which of the following would be a reasonably efficient technique for confirming the diagnosis of CML? A) searching for the number of telomeric sequences on chromosome 22 B) looking for a Ph' chromosome in a peripheral blood smear C) enzyme assay for thymine kinase activity D) FISH study to determine the chromosomal location of all chromosome 22 fragments E) identification of the disease phenotype in review of the patient's records

D) FISH study to determine the chromosomal location of all chromosome 22 fragments

23) Which of the three types of viruses shown above would you expect to include glycoproteins? *image 1 A) I only B) II only C) III only D) I and II only E) all three

D) I and II only

In recombinant DNA methods, the term vector can refer to A) the enzyme that cuts DNA into restriction fragments. B) the sticky end of a DNA fragment. C) a SNP marker. D) a plasmid used to transfer DNA into a living cell. E) a DNA probe used to identify a particular gene.

D) a plasmid used to transfer DNA into a living cell.

CML (chronic myelogenous leukemia) results from a translocation between human chromosomes 9 and 22. The resulting chromosome 22 is significantly shorter than usual, and it is known as a Philadelphia (Ph') chromosome. The junction at the site of the translocation causes overexpression of a thymine kinase receptor. A new drug (Gleevec or imatinib) has been found to inhibit the disease if the patient is treated early. Why would Gleevec most probably cause remission of the disease? A) It reverses the chromosomal translocation. B) It eliminates the Ph' chromosome. C) It removes Ph'-containing progenitor cells. D) The drug inhibits the replication of the affected chromosome. E) The drug inhibits the specific thymine kinase receptor.

E) The drug inhibits the specific thymine kinase receptor.

Why is it so important to be able to amplify DNA fragments when studying genes? A) DNA fragments are too small to use individually. B) A gene may represent only a millionth of the cell's DNA. C) Restriction enzymes cut DNA into fragments that are too small. D) A clone requires multiple copies of each gene per clone. E) It is important to have multiple copies of DNA in the case of laboratory error

B) A gene may represent only a millionth of the cell's DNA.

The DNA fragments making up a genomic library are generally contained in A) BACs. B) recombinant viral RNA. C) individual wells. D) DNA-RNA hybrids. E) radioactive eukaryotic cells.

BACs

In 1971, David Baltimore described a scheme for classifying viruses based on how the virus produces mRNA. The table below shows the results of testing five viruses for nuclease specificity, the ability of the virus to act as an mRNA, and presence (+) or absence (-) of its own viral polymerase (SEE IMAGE) 35) Based on the above table, which virus meets the Baltimore requirements for a retrovirus? *image 3 A) A B) B C) C D) D E) E

D) D

Which of the following are probably siblings? *image 5 A) A and B B) A and C C) A and D D) C and D E) B and D

D) c and d

Which of the following is most closely identical to the formation of twins? A) cell cloning B) therapeutic cloning C) use of adult stem cells D) embryo transfer E) organismal cloning

E) organismal cloning

19) Which of the following is the best predictor of how much damage a virus causes? A) ability of the infected cell to undergo normal cell division B) ability of the infected cell to carry on translation C) whether the infected cell produces viral protein D) whether the viral mRNA can be transcribed E) how much toxin the virus produces

A) ability of the infected cell to undergo normal cell division

3) The host range of a virus is determined by A) the enzymes carried by the virus. B) whether its nucleic acid is DNA or RNA. C) the proteins in the host's cytoplasm. D) the enzymes produced by the virus before it infects the cell. E) the proteins on its surface and that of the host.

E) the proteins on its surface and that of the host.

Which of the following best describes the complete sequence of steps occurring during every cycle of PCR? 1. The primers hybridize to the target DNA. 2. The mixture is heated to a high temperature to denature the double-stranded target DNA. 3. Fresh DNA polymerase is added. 4. DNA polymerase extends the primers to make a copy of the target DNA. A) 2, 1, 4 B) 1, 3, 2, 4 C) 3, 4, 1, 2 D) 3, 4, 2 E) 2, 3, 4

A) 2, 1, 4

In 1971, David Baltimore described a scheme for classifying viruses based on how the virus produces mRNA. The table below shows the results of testing five viruses for nuclease specificity, the ability of the virus to act as an mRNA, and presence (+) or absence (-) of its own viral polymerase (SEE IMAGE) 36) Based on the above table, which virus meets the requirements for a bacteriophage? *image 3 A) A B) B C) C D) D E) E

A) A

In recent times, it has been shown that adult cells can be induced to become pluripotent stem cells (iPS). In order to make this conversion, what has been done to the adult cells? A) A retrovirus is used to introduce four specific regulatory genes. B) The adult stem cells must be fused with embryonic cells. C) Cytoplasm from embryonic cells is injected into the adult cells. D) An adenovirus vector is used to transfer embryonic gene products into adult cells. E) The nucleus of an embryonic cell is used to replace the nucleus of an adult cell.

A) A retrovirus is used to introduce four specific regulatory genes.

You isolate an infectious substance that is capable of causing disease in plants, but you do not know whether the infectious agent is a bacterium, virus, viroid, or prion. You have four methods at your disposal that you can use to analyze the substance in order to determine the nature of the infectious agent. I. treating the substance with nucleases that destroy all nucleic acids and then determining whether it is still infectious II. filtering the substance to remove all elements smaller than what can be easily seen under a light microscope III. culturing the substance by itself on nutritive medium, away from any plant cells IV. treating the sample with proteases that digest all proteins and then determining whether it is still infectious 37) Which treatment could definitively determine whether or not the component is a viroid? A) I B) II C) III D) IV E) first II and then III

A) I

The reason for using Taq polymerase for PCR is that A) it is heat stable and can withstand the temperature changes of the cycler. B) only minute amounts are needed for each cycle of PCR. C) it binds more readily than other polymerases to primer. D) it has regions that are complementary to primers. E) All of these are correct.

A) It is heat stable and can withstand the temperature changes of the cycler.

Scientists developed a set of guidelines to address the safety of DNA technology. Which of the following is one of the adopted safety measures? A) Microorganisms used in recombinant DNA experiments are genetically crippled to ensure that they cannot survive outside of the laboratory. B) Genetically modified organisms are not allowed to be part of our food supply. C) Transgenic plants are engineered so that the plant genes cannot hybridize. D) Experiments involving HIV or other potentially dangerous viruses have been banned. E) Recombinant plasmids cannot be replicated.

A) Microorganisms used in recombinant DNA experiments are genetically crippled to ensure that they cannot survive outside of the laboratory.

A researcher is using adult stem cells and comparing them to other adult cells from the same tissue. Which of the following is a likely finding? A) The cells from the two sources exhibit different patterns of DNA methylation. B) Adult stem cells have more DNA nucleotides than their counterparts. C) The two kinds of cells have virtually identical gene expression patterns in microarrays. D) The nonstem cells have fewer repressed genes. E) The nonstem cells have lost the promoters for more genes.

A) The cells from the two sources exhibit different patterns of DNA methylation.

Which of the following modifications is least likely to alter the rate at which a DNA fragment moves through a gel during electrophoresis? A) altering the nucleotide sequence of the DNA fragment B) methylating the cytosine bases within the DNA fragment C) increasing the length of the DNA fragment D) decreasing the length of the DNA fragment E) neutralizing the negative charges within the DNA fragment

A) altering the nucleotide sequence of the DNA fragment

How does a bacterial cell protect its own DNA from restriction enzymes? A) by adding methyl groups to adenines and cytosines B) by using DNA ligase to seal the bacterial DNA into a closed circle C) by adding histones to protect the double-stranded DNA D) by forming "sticky ends" of bacterial DNA to prevent the enzyme from attaching E) by reinforcing the bacterial DNA structure with covalent phosphodiester bonds

A) by adding methyl groups to adenines and cytosines

4) Most human-infecting viruses are maintained in the human population only. However, a zoonosis is a disease that is transmitted from other vertebrates to humans, at least sporadically, without requiring viral mutation. Which of the following is the best example of a zoonosis? A) rabies B) herpesvirus C) smallpox D) HIV E) hepatitis virus

A) rabies

A researcher has used in vitro mutagenesis to mutate a cloned gene and then has reinserted this into a cell. In order to have the mutated sequence disable the function of the gene, what must then occur? A) recombination resulting in replacement of the wild type with the mutated gene B) use of a microarray to verify continued expression of the original gene C) replication of the cloned gene using a bacterial plasmid D) transcription of the cloned gene using a BAC E) attachment of the mutated gene to an existing mRNA to be translated

A) recombination resulting in replacement of the wild type with the mutated gene

DNA fragments from a gel are transferred to a nitrocellulose paper during the procedure called Southern blotting. What is the purpose of transferring the DNA from a gel to a nitrocellulose paper? A) to attach the DNA fragments to a permanent substrate B) to separate the two complementary DNA strands C) to transfer only the DNA that is of interest D) to prepare the DNA for digestion with restriction enzymes E) to separate out the PCRs

A) to attach the DNA fragments to a permanent substrate

17) The difference between vertical and horizontal transmission of plant viruses is that A) vertical transmission is transmission of a virus from a parent plant to its progeny, and horizontal transmission is one plant spreading the virus to another plant. B) vertical transmission is the spread of viruses from upper leaves to lower leaves of the plant, and horizontal transmission is the spread of a virus among leaves at the same general level. C) vertical transmission is the spread of viruses from trees and tall plants to bushes and other smaller plants, and horizontal transmission is the spread of viruses among plants of similar size. D) vertical transmission is the transfer of DNA from one type of plant virus to another, and horizontal transmission is the exchange of DNA between two plant viruses of the same type. E) vertical transmission is the transfer of DNA from a plant of one species to a plant of a different species, and horizontal transmission is the spread of viruses among plants of the same species.

A) vertical transmission is transmission of a virus from a parent plant to its progeny, and horizontal transmission is one plant spreading the virus to another plant.

Reproductive cloning of human embryos is generally considered unethical. However, on the subject of therapeutic cloning there is a wider divergence of opinion. Which of the following is a likely explanation? A) Use of adult stem cells is likely to produce more cell types than use of embryonic stem cells. B) Cloning to produce embryonic stem cells may lead to great medical benefits for many. C) Cloning to produce stem cells relies on a different initial procedure than reproductive cloning. D) A clone that lives until the blastocyst stage does not yet have human DNA. E) No embryos would be destroyed in the process of therapeutic cloning.

B) Cloning to produce embryonic stem cells may lead to great medical benefits for many.

Which of the following statements is most likely true? *image 5 A) D is the child of A and C. B) D is the child of A and B. C) D is the child of B and C. D) A is the child of C and D. E) B is the child of A and C.

B) D is the child of A and B.

9) Why do RNA viruses appear to have higher rates of mutation? A) RNA nucleotides are more unstable than DNA nucleotides. B) Replication of their genomes does not involve proofreading. C) RNA viruses replicate faster. D) RNA viruses can incorporate a variety of nonstandard bases. E) RNA viruses are more sensitive to mutagens.

B) Replication of their genomes does not involve proofreading.

15) Which of the following describes plant virus infections? A) They can be controlled by the use of antibiotics. B) They are spread via the plasmodesmata. C) They have little effect on plant growth. D) They are seldom spread by insects. E) They can never be passed vertically.

B) They are spread via the plasmodesmata.

Which of the following is true of embryonic stem cells but not of adult stem cells? A) They can differentiate into many cell types. B) They make up the majority of cells of the tissue from which they are derived. C) They can continue to replicate for an indefinite period. D) They can provide enormous amounts of information about the process of gene regulation. E) One aim of using them is to provide cells for repair of diseased tissue.

B) They make up the majority of cells of the tissue from which they are derived.

16) Which of the following represents a difference between viruses and viroids? A) Viruses infect many types of cells, whereas viroids infect only prokaryotic cells. B) Viruses have capsids composed of protein, whereas viroids have no capsids. C) Viruses contain introns, whereas viroids have only exons. D) Viruses always have genomes composed of DNA, whereas viroids always have genomes composed of RNA. E) Viruses cannot pass through plasmodesmata, whereas viroids can.

B) Viruses have capsids composed of protein, whereas viroids have no capsids.

2) Viral envelopes can best be analyzed with which of the following techniques? A) transmission electron microscopy B) antibodies against specific proteins not found in the host membranes C) staining and visualization with the light microscope D) use of plaque assays for quantitative measurement of viral titer E) immunofluorescent tagging of capsid proteins

B) antibodies against specific proteins not found in the host membranes

To introduce a particular piece of DNA into an animal cell, such as that of a mouse, you would find more probable success with which of the following methods? A) the shotgun approach B) electroporation followed by recombination C) introducing a plasmid into the cell D) infecting the mouse cell with a Ti plasmid E) transcription and translation

B) electroporation followed by recombination

47) RNA viruses require their own supply of certain enzymes because A) host cells rapidly destroy the viruses. B) host cells lack enzymes that can replicate the viral genome. C) these enzymes translate viral mRNA into proteins. D) these enzymes penetrate host cell membranes. E) these enzymes cannot be made in host cells.

B) host cells lack enzymes that can replicate the viral genome.

Genetically engineered plants A) are more difficult to engineer than animals. B) include a transgenic rice plant that can help prevent vitamin A deficiency. C) are being rapidly developed, but traditional plant breeding programs are still the only method used to develop new plants. D) are able to fix nitrogen themselves. E) are banned throughout the world.

B) include a transgenic rice plant that can help prevent vitamin A deficiency.

The herpes viruses are very important enveloped DNA viruses that cause disease in all vertebrate species and in some invertebrates such as oysters. Some of the human ones are herpes simplex (HSV) I and II, causing facial and genital lesions, and the varicella-zoster (VSV), causing chicken pox and shingles. Each of these three actively infect nervous tissue. Primary infections are fairly mild, but the virus is not then cleared from the host; rather, viral genomes are maintained in cells in a latent phase. The virus can then reactivate, replicate again, and be infectious to others. 40) If scientists are trying to use what they know about HSV to devise a means of protecting other people from being infected, which of the following would have the best chance of lowering the number of new cases of infection? A) vaccination of all persons with preexisting cases B) interference with new viral replication in preexisting cases C) treatment of the HSV lesions to shorten the breakout D) medication that destroys surface HSV before it gets to neurons E) education about avoiding sources of infection

B) interference with new viral replication in preexisting cases

In 1971, David Baltimore described a scheme for classifying viruses based on how the virus produces mRNA. The table below shows the results of testing five viruses for nuclease specificity, the ability of the virus to act as an mRNA, and presence (+) or absence (-) of its own viral polymerase (SEE IMAGE) 34) Given Baltimore's scheme, a positive sense single-stranded RNA virus such as the polio virus would be most closely related to which of the following? *image 3 A) T-series bacteriophages B) retroviruses that require a DNA intermediate C) single-stranded DNA viruses such as herpes viruses D) nonenveloped double-stranded RNA viruses E) linear double-stranded DNA viruses such as adenoviruses

B) retroviruses that require a DNA intermediate

Some viruses can be crystallized and their structures analyzed. One such virus is Desmodium, or yellow mottle virus, which infects beans. This is a member of the tymovirus group and has a single-stranded RNA genome of ~6,300 nucleotides. Its virion is 25—30 nm in diameter, and is made up of 180 copies of a single capsid protein that self-associate to form each capsomere, which has icosahedral symmetry with 20 facets. 31) In a cell-free system, what other components would you have to provide for this virus to express its genes? A) ribosomes, tRNAs and amino acids B) ribosomes, tRNAs, amino acids, and GTP C) RNA nucleotides and GTP D) RNA nucleotides, RNA polymerase, and GTP E) bean cell enzymes

B) ribosomes, tRNAs, amino acids, and GTP

RNAi methodology uses double-stranded pieces of RNA to trigger a breakdown or blocking of mRNA. For which of the following might it more possibly be useful? A) to raise the rate of production of a needed digestive enzyme B) to decrease the production from a harmful gain-of-function mutated gene C) to destroy an unwanted allele in a homozygous individual D) to form a knockout organism that will not pass the deleted sequence to its progeny E) to raise the concentration of a desired protein

B) to decrease the production from a harmful gain-of-function mutated gene

You isolate an infectious substance that is capable of causing disease in plants, but you do not know whether the infectious agent is a bacterium, virus, viroid, or prion. You have four methods at your disposal that you can use to analyze the substance in order to determine the nature of the infectious agent. I. treating the substance with nucleases that destroy all nucleic acids and then determining whether it is still infectious II. filtering the substance to remove all elements smaller than what can be easily seen under a light microscope III. culturing the substance by itself on nutritive medium, away from any plant cells IV. treating the sample with proteases that digest all proteins and then determining whether it is still infectious 38) If you already knew that the infectious agent was either bacterial or viral, which treatment would allow you to distinguish between these two possibilities? A) I B) II C) III D) IV E) either II or IV

C) III

What is the most logical sequence of steps for splicing foreign DNA into a plasmid and inserting the plasmid into a bacterium? I. Transform bacteria with a recombinant DNA molecule. II. Cut the plasmid DNA using restriction enzymes. III. Extract plasmid DNA from bacterial cells. IV. Hydrogen-bond the plasmid DNA to nonplasmid DNA fragments. V. Use ligase to seal plasmid DNA to nonplasmid DNA. A) I, II, IV, III, V B) II, III, V, IV, I C) III, II, IV, V, I D) III, IV, V, I, II E) IV, V, I, II, III

C) III, II, IV, V, I

Silencing of selected genes is often done using RNA interference (RNAi). Which of the following questions would not be answered with this process? A) What is the function of gene 432 in this species of annelid? B) What will happen in this insect's digestion if gene 173 is not able to be translated? C) Is gene HA292 responsible for this disorder in humans? D) Will the disabling of this gene in Drosophila and in a mouse cause similar results? E) Is the gene on Drosophila chromosome 2L at this locus responsible for part of its production of nitrogen waste?

C) Is gene HA292 responsible for this disorder in humans?

Pax-6 is a gene that is involved in eye formation in many invertebrates, such as Drosophila. Pax-6 is found as well in vertebrates. A Pax-6 gene from a mouse can be expressed in a fly and the protein (PAX-6) leads to a compound fly eye. This information suggests which of the following? A) Pax-6 genes are identical in nucleotide sequence. B) PAX-6 proteins have identical amino acid sequences. C) Pax-6 is highly conserved and shows shared evolutionary ancestry. D) PAX-6 proteins are different for formation of different kinds of eyes. E) PAX-6 from a mouse can function in a fly, but a fly's Pax-6 gene cannot function in a mouse.

C) Pax-6 is highly conserved and shows shared evolutionary ancestry

Poliovirus is a positive-sense RNA virus of the picornavirus group. At its 5' end, the RNA genome has a viral protein (VPg) instead of a 5' cap. This is followed by a nontranslated leader sequence, and then a single long protein coding region (~7,000 nucleotides), followed by a poly-A tail. Observations were made that used radioactive amino acid analogues. Short period use of the radioactive amino acids result in labeling of only very long proteins, while longer periods of labeling result in several different short polypeptides. 33) What conclusion is most consistent with the results of the radioactive labeling experiment? A) The host cell cannot translate viral protein with the amino acid analogues. B) Host cell ribosomes only translate the viral code into short polypeptides. C) The RNA is only translated into a single long polypeptide, which is then cleaved into shorter ones. D) The RNA is translated into short polypeptides, which are subsequently assembled into large ones. E) The large radioactive polypeptides are coded by the host, whereas the short ones are coded for by the virus.

C) The RNA is only translated into a single long polypeptide, which is then cleaved into shorter ones.

One successful form of gene therapy has involved delivery of an allele for the enzyme adenosine deaminase (ADA) to bone marrow cells of a child with SCID, and delivery of these engineered cells back to the bone marrow of the affected child. What is one major reason for the success of this procedure as opposed to many other efforts at gene therapy? A) The engineered bone marrow cells from this patient can be used for any other SCID patient. B) The ADA-introduced allele causes all other ADA-negative cells to die. C) The engineered cells, when reintroduced into the patient, find their way back to the bone marrow. D) No vector is required to introduce the allele into ADA-negative cells. E) The immune system fails to recognize cells with the variant gene.

C) The engineered cells, when reintroduced into the patient, find their way back to the bone marrow.

8) Which of the following statements describes the lysogenic cycle of lambda (λ) phage? A) After infection, the viral genes immediately turn the host cell into a lambda-producing factory, and the host cell then lyses. B) Most of the prophage genes are activated by the product of a particular prophage gene. C) The phage genome replicates along with the host genome. D) Certain environmental triggers can cause the phage to exit the host genome, switching from the lytic to the lysogenic. E) The phage DNA is incorporated by crossing over into any nonspecific site on the host cell's DNA.

C) The phage genome replicates along with the host genome.

11) A researcher lyses a cell that contains nucleic acid molecules and capsomeres of tobacco mosaic virus (TMV). The cell contents are left in a covered test tube overnight. The next day this mixture is sprayed on tobacco plants. Which of the following would be expected to occur? A) The plants would develop some but not all of the symptoms of the TMV infection. B) The plants would develop symptoms typically produced by viroids. C) The plants would develop the typical symptoms of TMV infection. D) The plants would not show any disease symptoms. E) The plants would become infected, but the sap from these plants would be unable to infect other plants.

C) The plants would develop the typical symptoms of TMV infection.

Which of the following describes the transfer of polypeptide sequences to a membrane to analyze gene expression? A) Southern blotting B) Northern blotting C) Western blotting D) Eastern blotting E) RT-PCR

C) Western blotting

The major advantage of using artificial chromosomes such as YACs and BACs for cloning genes is that A) plasmids are unable to replicate in cells. B) only one copy of a plasmid can be present in any given cell, whereas many copies of a YAC or BAC can coexist in a single cell. C) YACs and BACs can carry much larger DNA fragments than ordinary plasmids can. D) YACs and BACs can be used to express proteins encoded by inserted genes, but plasmids cannot. E) All of these are correct.

C) YACs and BACs can carry much larger DNA fragments than ordinary plasmids can.

A student wishes to clone a sequence of DNA of ~200 kb. Which vector would be appropriate? A) a plasmid B) a typical bacteriophage C) a BAC D) a plant virus E) a large polypeptide

C) a BAC

For a particular microarray assay (DNA chip), cDNA has been made from the mRNAs of a dozen patients' breast tumor biopsies. The researchers will be looking for A) a particular gene that is amplified in all or most of the patient samples. B) a pattern of fluorescence that indicates which cells are overproliferating. C) a pattern shared among some or all of the samples that indicates gene expression differing from control samples. D) a group of cDNAs that act differently from those on the rest of the grid. E) a group of cDNAs that match those in non-breast cancer control samples from the same population.

C) a pattern shared among some or all of the samples that indicates gene expression differing from control samples.

Which enzyme was used to produce the molecule in Figure 20.1? *image 4 A) ligase B) transcriptase C) a restriction enzyme D) RNA polymerase E) DNA polymerase

C) a restriction enzyme

Which of the following problems with animal cloning might result in premature death of the clones? A) use of pluripotent instead of totipotent stem cells B) use of nuclear DNA as well as mtDNA C) abnormal regulation due to variant methylation D) the indefinite replication of totipotent stem cells E) abnormal immune function due to bone marrow dysfunction

C) abnormal regulation due to variant methylation

DNA microarrays have made a huge impact on genomic studies because they A) can be used to eliminate the function of any gene in the genome. B) can be used to introduce entire genomes into bacterial cells. C) allow the expression of many or even all of the genes in the genome to be compared at once. D) allow physical maps of the genome to be assembled in a very short time. E) dramatically enhance the efficiency of restriction enzymes.

C) allow the expression of many or even all of the genes in the genome to be compared at once.

The herpes viruses are very important enveloped DNA viruses that cause disease in all vertebrate species and in some invertebrates such as oysters. Some of the human ones are herpes simplex (HSV) I and II, causing facial and genital lesions, and the varicella-zoster (VSV), causing chicken pox and shingles. Each of these three actively infect nervous tissue. Primary infections are fairly mild, but the virus is not then cleared from the host; rather, viral genomes are maintained in cells in a latent phase. The virus can then reactivate, replicate again, and be infectious to others. 42) In order to be able to remain latent in an infected live cell, HSV must be able to shut down what process? A) DNA replication B) transcription of viral genes C) apoptosis of a virally infected cell D) all immune responses E) interaction with histones

C) apoptosis of a virally infected cell

A principal problem with inserting an unmodified mammalian gene into a BAC, and then getting that gene expressed in bacteria, is that A) prokaryotes use a different genetic code from that of eukaryotes. B) bacteria translate polycistronic messages only. C) bacteria cannot remove eukaryotic introns. D) bacterial RNA polymerase cannot make RNA complementary to mammalian DNA. E) bacterial DNA is not found in a membrane-bounded nucleus and is therefore incompatible with mammalian DNA.

C) bacteria cannot remove eukaryotic introns.

45) To cause a human pandemic, the H5N1 avian flu virus would have to A) spread to primates such as chimpanzees. B) develop into a virus with a different host range. C) become capable of human-to-human transmission. D) arise independently in chickens in North and South America. E) become much more pathogenic.

C) become capable of human-to-human transmission.

6) In many ways, the regulation of the genes of a particular group of viruses will be similar to the regulation of the host genes. Therefore, which of the following would you expect of the genes of the bacteriophage? A) regulation via acetylation of histones B) positive control mechanisms rather than negative C) control of more than one gene in an operon D) reliance on transcription activators E) utilization of eukaryotic polymerases

C) control of more than one gene in an operon

Assume that you are trying to insert a gene into a plasmid. Someone gives you a preparation of genomic DNA that has been cut with restriction enzyme X. The gene you wish to insert has sites on both ends for cutting by restriction enzyme Y. You have a plasmid with a single site for Y, but not for X. Your strategy should be to A) insert the fragments cut with restriction enzyme X directly into the plasmid without cutting the plasmid. B) cut the plasmid with restriction enzyme X and insert the fragments cut with restriction enzyme Y into the plasmid. C) cut the DNA again with restriction enzyme Y and insert these fragments into the plasmid cut with the same enzyme. D) cut the plasmid twice with restriction enzyme Y and ligate the two fragments onto the ends of the DNA fragments cut with restriction enzyme X. E) cut the plasmid with restriction enzyme X and then insert the gene into the plasmid.

C) cut the DNA again with restriction enzyme Y and insert these fragments into the plasmid cut with the same enzyme.

43) Which of the following characteristics, structures, or processes is common to both bacteria and viruses? A) metabolism B) ribosomes C) genetic material composed of nucleic acid D) cell division E) independent existence

C) genetic material composed of nucleic acid

Which of the following techniques used to analyze gene function depends on the specificity of DNA base complementarity? A) Northern blotting B) use of RNAi C) in vitro mutagenesis D) in situ hybridization E) restriction fragment analysis

C) in vitro mutagenesis

A gene that contains introns can be made shorter (but remain functional) for genetic engineering purposes by using A) RNA polymerase to transcribe the gene. B) a restriction enzyme to cut the gene into shorter pieces. C) reverse transcriptase to reconstruct the gene from its mRNA. D) DNA polymerase to reconstruct the gene from its polypeptide product. E) DNA ligase to put together fragments of the DNA that code for a particular polypeptide.

C) reverse transcriptase to reconstruct the gene from its mRNA.

In large scale, genome-wide association studies in humans, correlation is sought between A) lengthy sequences that might be shared by most members of a population. B) single nucleotide polymorphisms found only in persons with a particular disorder. C) single nucleotide polymorphisms found in families with a particular introns sequence. D) single nucleotide polymorphisms in two or more adjacent genes. E) large inversions that displace the centromere.

C) single nucleotide polymorphisms found in families with a particular introns sequence.

Poliovirus is a positive-sense RNA virus of the picornavirus group. At its 5' end, the RNA genome has a viral protein (VPg) instead of a 5' cap. This is followed by a nontranslated leader sequence, and then a single long protein coding region (~7,000 nucleotides), followed by a poly-A tail. Observations were made that used radioactive amino acid analogues. Short period use of the radioactive amino acids result in labeling of only very long proteins, while longer periods of labeling result in several different short polypeptides. 32) What part of the poliovirus would first interact with host cell ribosomes to mediate translation? A) the poly-A tail B) the leader sequence C) the VPg protein D) the AUG in the leader sequence E) the AUG at the start of the coding sequence

C) the VPg protein

As genetic technology makes testing for a wide variety of genotypes possible, which of the following is likely to be an increasingly troublesome issue? A) use of genotype information to provide positive identification of criminals B) using technology to identify genes that cause criminal behaviors C) the need to legislate for the protection of the privacy of genetic information D) discrimination against certain racial groups because of major genetic differences E) alteration of human phenotypes to prevent early disease

C) the need to legislate for the protection of the privacy of genetic information

Some viruses can be crystallized and their structures analyzed. One such virus is Desmodium, or yellow mottle virus, which infects beans. This is a member of the tymovirus group and has a single-stranded RNA genome of ~6,300 nucleotides. Its virion is 25—30 nm in diameter, and is made up of 180 copies of a single capsid protein that self-associate to form each capsomere, which has icosahedral symmetry with 20 facets. 30) If this virus has a positive RNA strand as its genome, it begins the infection by using this strand as mRNA. Therefore, which of the following do you expect to be able to measure? A) replication rate B) transcription rate C) translation rate D) accumulation of new ribosomes E) formation of new transcription factors

C) translation rate

Some viruses can be crystallized and their structures analyzed. One such virus is Desmodium, or yellow mottle virus, which infects beans. This is a member of the tymovirus group and has a single-stranded RNA genome of ~6,300 nucleotides. Its virion is 25—30 nm in diameter, and is made up of 180 copies of a single capsid protein that self-associate to form each capsomere, which has icosahedral symmetry with 20 facets. 28) If this virus has capsomeres with 20 facets, how many proteins form each one? A) 1 B) 5 C) ~6 D) ~20 E) ~180

C) ~6

You isolate an infectious substance that is capable of causing disease in plants, but you do not know whether the infectious agent is a bacterium, virus, viroid, or prion. You have four methods at your disposal that you can use to analyze the substance in order to determine the nature of the infectious agent. I. treating the substance with nucleases that destroy all nucleic acids and then determining whether it is still infectious II. filtering the substance to remove all elements smaller than what can be easily seen under a light microscope III. culturing the substance by itself on nutritive medium, away from any plant cells IV. treating the sample with proteases that digest all proteins and then determining whether it is still infectious 39) Which treatment would you use to determine if the agent is a prion? A) I only B) II only C) III only D) IV only E) either I or IV

D) IV only

46) A bacterium is infected with an experimentally constructed bacteriophage composed of the T2 phage protein coat and T4 phage DNA. The new phages produced would have A) T2 protein and T4 DNA. B) T2 protein and T2 DNA. C) a mixture of the DNA and proteins of both phages. D) T4 protein and T4 DNA. E) T4 protein and T2 DNA.

D) T4 protein and T4 DNA.

The herpes viruses are very important enveloped DNA viruses that cause disease in all vertebrate species and in some invertebrates such as oysters. Some of the human ones are herpes simplex (HSV) I and II, causing facial and genital lesions, and the varicella-zoster (VSV), causing chicken pox and shingles. Each of these three actively infect nervous tissue. Primary infections are fairly mild, but the virus is not then cleared from the host; rather, viral genomes are maintained in cells in a latent phase. The virus can then reactivate, replicate again, and be infectious to others. 41) In electron micrographs of HSV infection, it can be seen that the intact virus initially reacts with cell surface proteoglycans, then with specific receptors. This is later followed by viral capsids docking with nuclear pores. Afterward, the capsids go from being full to being "empty." Which of the following best fits these observations? A) Viral capsids are needed for the cell to become infected; only the capsids enter the nucleus. B) The viral envelope is not required for infectivity, since the envelope does not enter the nucleus. C) Only the genetic material of the virus is involved in the cell's infectivity, and is injected like the genome of a phage. D) The viral envelope mediates entry into the cell, the capsid entry into the nuclear membrane, and the genome is all that enters the nucleus. E) The viral capsid mediates entry into the cell, and only the genomic DNA enters the nucleus, where it may or may not replicate.

D) The viral envelope mediates entry into the cell, the capsid entry into the nuclear membrane, and the genome is all that enters the nucleus.

In animals, what is the difference between reproductive cloning and therapeutic cloning? A) Reproductive cloning uses totipotent cells, whereas therapeutic cloning does not. B) Reproductive cloning uses embryonic stem cells, whereas therapeutic cloning does not. C) Therapeutic cloning uses nuclei of adult cells transplanted into enucleated nonfertilized eggs. D) Therapeutic cloning supplies cells for repair of diseased or injured organs.

D) Therapeutic cloning supplies cells for repair of diseased or injured organs.

Which of the following is one of the technical reasons why gene therapy is problematic? A) Most cells with an engineered gene do not produce gene product. B) Most cells with engineered genes overwhelm other cells in a tissue. C) Cells with transferred genes are unlikely to replicate. D) Transferred genes may not have appropriately controlled activity. E) mRNA from transferred genes cannot be translated.

D) Transferred genes may not have appropriately controlled activity.

The first cloned cat, called Carbon Copy, was a calico, but she looked significantly different from her female parent. Why? A) The environment, as well as genetics, affects phenotypic variation. B) Fur color genes in cats are influenced by differential acetylation patterns. C) Cloned animals have been found to have a higher frequency of transposon activation D) X inactivation in the embryo is random and produces different patterns. E) The telomeres of the parent's chromosomes were shorter than those of an embryo.

D) X inactivation in the embryo is random and produces different patterns.

Sequencing an entire genome, such as that of C. elegans, a nematode, is most important because A) it allows researchers to use the sequence to build a "better" nematode, which is resistant to disease. B) it allows research on a group of organisms we do not usually care much about. C) the nematode is a good animal model for trying out cures for viral illness. D) a sequence that is found to have a particular function in the nematode is likely to have a closely related function in vertebrates. E) a sequence that is found to have no introns in the nematode genome is likely to have acquired the introns from higher organisms.

D) a sequence that is found to have a particular function in the nematode is likely to have a closely related function in vertebrates.

5) Which of the following accounts for someone who has had a herpesvirus-mediated cold sore or genital sore getting flare-ups for the rest of his or her life? A) re-infection by a closely related herpesvirus of a different strain B) re-infection by the same herpesvirus strain C) co-infection with an unrelated virus that causes the same symptoms D) copies of the herpesvirus genome permanently maintained in host nuclei E) copies of the herpesvirus genome permanently maintained in host cell cytoplasm

D) copies of the herpesvirus genome permanently maintained in host nuclei

In 1997, Dolly the sheep was cloned. Which of the following processes was used? A) use of mitochondrial DNA from adult female cells of another ewe B) replication and dedifferentiation of adult stem cells from sheep bone marrow C) separation of an early stage sheep blastula into separate cells, one of which was incubated in a surrogate ewe D) fusion of an adult cell's nucleus with an enucleated sheep egg, followed by incubation in a surrogate E) isolation of stem cells from a lamb embryo and production of a zygote equivalent

D) fusion of an adult cell's nucleus with an enucleated sheep egg, followed by incubation in a surrogate

A eukaryotic gene has "sticky ends" produced by the restriction endonuclease EcoRI. The gene is added to a mixture containing EcoRI and a bacterial plasmid that carries two genes conferring resistance to ampicillin and tetracycline. The plasmid has one recognition site for EcoRI located in the tetracycline resistance gene. This mixture is incubated for several hours, exposed to DNA ligase, and then added to bacteria growing in nutrient broth. The bacteria are allowed to grow overnight and are streaked on a plate using a technique that produces isolated colonies that are clones of the original. Samples of these colonies are then grown in four different media: nutrient broth plus ampicillin, nutrient broth plus tetracycline, nutrient broth plus ampicillin and tetracycline, and nutrient broth without antibiotics. Bacteria that contain the plasmid, but not the eukaryotic gene, would grow A) in the nutrient broth plus ampicillin, but not in the broth containing tetracycline. B) only in the broth containing both antibiotics. C) in the broth containing tetracycline, but not in the broth containing ampicillin. D) in all four types of broth. E) in the nutrient broth without antibiotics only.

D) in all four types of broth.

18) What are prions? A) mobile segments of DNA B) tiny molecules of RNA that infect plants C) viral DNA that has had to attach itself to the host genome D) misfolded versions of normal brain protein E) viruses that invade bacteria

D) misfolded versions of normal brain protein

44) Emerging viruses arise by A) mutation of existing viruses. B) the spread of existing viruses to new host species. C) the spread of existing viruses more widely within their host species. D) mutation of existing viruses, the spread of existing viruses to new host species, and the spread of existing viruses more widely within their host species. E) none of these.

D) mutation of existing viruses, the spread of existing viruses to new host species, and the spread of existing viruses more widely within their host species.

1) Viral genomes vary greatly in size and may include from four genes to several hundred genes. Which of the following viral features is most apt to correlate with the size of the genome? A) size of the viral capsomeres B) RNA versus DNA genome C) double- versus single-strand genomes D) size and shape of the capsid E) glycoproteins of the envelope

D) size and shape of the capsid

Why might a laboratory be using dideoxy nucleotides? A) to separate DNA fragments B) to clone the breakpoints of cut DNA C) to produce cDNA from mRNA D) to sequence a DNA fragment E) to visualize DNA expression

D) to sequence a DNA fragment

21) Which of the following series best reflects what we know about how the flu virus moves between species? A) An avian flu virus undergoes several mutations and rearrangements such that it is able to be transmitted to other birds and then to humans. B) The flu virus in a pig is mutated and replicated in alternate arrangements so that humans who eat the pig products can be infected. C) A flu virus from a human epidemic or pandemic infects birds; the birds replicate the virus differently and then pass it back to humans. D) An influenza virus gains new sequences of DNA from another virus, such as a herpesvirus; this enables it to be transmitted to a human host. E) An animal such as a pig is infected with more than one virus, genetic recombination occurs, the new virus mutates and is passed to a new species such as a bird, the virus mutates and can be transmitted to humans.

E) An animal such as a pig is infected with more than one virus, genetic recombination occurs, the new virus mutates and is passed to a new species such as a bird, the virus mutates and can be transmitted to humans.

Which of the following uses reverse transcriptase to make cDNA followed by amplification? A) Southern blotting B) Northern blotting C) Western blotting D) Eastern blotting E) RT-PCR

E) RT-PCR

Why are BACs preferred today rather than bacteriophages for making genomic libraries? A) The BAC carries more DNA. B) The BAC can carry entire genes and their regulatory elements. C) Larger BACs are easier to store. D) The BAC can carry entire genes and their regulatory elements, and larger BACs are easier to store. E) The BAC carries more DNA, the BAC can carry entire genes and their regulatory elements, and larger BACs are easier to store.

E) The BAC carries more DNA, the BAC can carry entire genes and their regulatory elements, and larger BACs are easier to store.

In order to identify a specific restriction fragment using a probe, what must be done? A) The fragments must be separated by electrophoresis. B) The fragments must be treated with heat or chemicals to separate the strands of the double helix. C) The probe must be hybridized with the fragment. D) The fragments must be separated by electrophoresis and the fragments must be treated with heat or chemicals to separate the strands of the double helix. E) The fragments must be separated by electrophoresis, the fragments must be treated with heat or chemicals to separate the strands of the double helix, and the probe must be hybridized with the fragment

E) The fragments must be separated by electrophoresis, the fragments must be treated with heat or chemicals to separate the strands of the double helix, and the probe must be hybridized with the fragment.

22) Which of the following is the most probable fate of a newly emerging virus that causes high mortality in its host? A) It is able to spread to a large number of new hosts quickly because the new hosts have no immunological memory of them. B) The new virus replicates quickly and undergoes rapid adaptation to a series of divergent hosts. C) A change in environmental conditions such as weather patterns quickly forces the new virus to invade new areas. D) Sporadic outbreaks will be followed almost immediately by a widespread pandemic. E) The newly emerging virus will die out rather quickly or will mutate to be far less lethal.

E) The newly emerging virus will die out rather quickly or will mutate to be far less lethal.

10) Most molecular biologists think that viruses originated from fragments of cellular nucleic acid. Which of the following observations supports this theory? A) Viruses contain either DNA or RNA. B) Viruses are enclosed in protein capsids rather than plasma membranes. C) Viruses can reproduce only inside host cells. D) Viruses can infect both prokaryotic and eukaryotic cells. E) Viral genomes are usually similar to the genome of the host cell.

E) Viral genomes are usually similar to the genome of the host cell.

A researcher needs to clone a sequence of part of a eukaryotic genome in order to express the sequence and to modify the polypeptide product. She would be able to satisfy these requirements by using which of the following vectors? A) a bacterial plasmid B) BAC to accommodate the size of the sequence C) a modified bacteriophage D) a human chromosome E) a YAC with appropriate cellular enzymes

E) a YAC with appropriate cellular enzymes

Let us suppose that someone is successful at producing induced pluripotent stem cells (iPS) for replacement of pancreatic insulin-producing cells for people with type 1 diabetes. Which of the following could still be problems? I. the possibility that, once introduced into the patient, the iPS cells produce nonpancreatic cells II. the failure of the iPS cells to take up residence in the pancreas III. the inability of the iPS cells to respond to appropriate regulatory signals A) I only B) II only C) III only D) I and II E) all of them

E) all of them

24) Which of the three types of viruses shown above would you expect to include a capsid(s)? *image 1 A) I only B) II only C) III only D) I and II only E) all three

E) all three

Yeast artificial chromosomes contain which of the following elements? A) centromeres only B) telomeres only C) origin of replication only D) centromeres and telomeres only E) centromeres, telomeres, and an origin of replication

E) centromeres, telomeres, and an origin of replication

Genetic engineering is being used by the pharmaceutical industry. Which of the following is not currently one of the uses? A) production of human insulin B) production of human growth hormone C) production of tissue plasminogen activator D) genetic modification of plants to produce vaccines E) creation of products that will remove poisons from the human body

E) creation of products that will remove poisons from the human body

26) In the figure, when new viruses are being assembled (IV), what mediates the assembly? *image 2 A) host cell chaperones B) assembly proteins coded for by the host nucleus C) assembly proteins coded for by the viral genes D) viral RNA intermediates E) nothing; they self-assemble

E) nothing; they self-assemble

A eukaryotic gene has "sticky ends" produced by the restriction endonuclease EcoRI. The gene is added to a mixture containing EcoRI and a bacterial plasmid that carries two genes conferring resistance to ampicillin and tetracycline. The plasmid has one recognition site for EcoRI located in the tetracycline resistance gene. This mixture is incubated for several hours, exposed to DNA ligase, and then added to bacteria growing in nutrient broth. The bacteria are allowed to grow overnight and are streaked on a plate using a technique that produces isolated colonies that are clones of the original. Samples of these colonies are then grown in four different media: nutrient broth plus ampicillin, nutrient broth plus tetracycline, nutrient broth plus ampicillin and tetracycline, and nutrient broth without antibiotics. Bacteria containing a plasmid into which the eukaryotic gene has integrated would grow in A) the nutrient broth only. B) the nutrient broth and the tetracycline broth only. C) the nutrient broth, the ampicillin broth, and the tetracycline broth. D) all four types of broth. E) the ampicillin broth and the nutrient broth.

E) the ampicillin broth and the nutrient broth.

Some viruses can be crystallized and their structures analyzed. One such virus is Desmodium, or yellow mottle virus, which infects beans. This is a member of the tymovirus group and has a single-stranded RNA genome of ~6,300 nucleotides. Its virion is 25—30 nm in diameter, and is made up of 180 copies of a single capsid protein that self-associate to form each capsomere, which has icosahedral symmetry with 20 facets. 29) How many nucleotides of the genome would you expect to find in one capsid? A) 1 B) ~6 C) ~20 D) ~180 E) ~6,300

E) ~6,300