Biology Review Sem 2 Test 2

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Some viruses can be crystallized and their structures analyzed. One such virus is yellow mottle virus, which infects beans. This virus has a single-stranded RNA genome containing about 6,300 nucleotides. Its capsid is 25-30 nm in diameter and contains 180 identical capsomeres. If the yellow mottle virus capsid has 20 facets, how many proteins form each facet? 20 1 180 9 5

9

You are a doctor in Egypt. Which of the following patients are you most likely to diagnose with schistosomiasis? A patient with anemia and blood in the urine. A patient with a rash on their chest and general fatigue. A patient with an irregular heart beat and high blood pressure. A patient with swollen lymph nodes in the neck and hair loss.

A patient with anemia and blood in the urine.

All of the statements below are true. Select the statement that best supports the view of most biologists that viruses are nonliving. An isolated virus is unable to replicate its genes or regenerate ATP. Viruses are obligate intracellular parasites. The viral genome may be single-stranded or double-stranded RNA or DNA.

An isolated virus is unable to replicate its genes or regenerate ATP.

How do prions, which are misfolded proteins, infect organisms? Prions enter brain cells and cause normal forms of the protein to refold into the prion form. Prions only arise through spontaneous mutation. They are not transmissible. Prions recruit ribosomes to make more copies of the wrong form of the protein. Prions enter brain cells through the lymphatic system and make copies of themselves. None of the listed responses is correct.

Prions enter brain cells and cause normal forms of the protein to refold into the prion form.

Why have so many people with Lassa been turned away from hospitals in Sierra Leone? It was thought they had Ebola and there were no beds available. It was unknown as to what the patients had. They were often diagnosed with malaria and sent home with treatment. They tested positive for Lassa, but were turned away due to a lack of treatment.

It was unknown as to what the patients had.

You are a doctor working in Sierra Leone. A patient presents with fever, vomiting, bleeding and a brain infection. Which would be best to diagnose? Ebola Lassa Either Lassa or Ebola. Neither Lassa nor Ebola.

Lassa

Which of the following is currently most likely to be fatal to a human? H5N8 H5N2 H5N1 Flu is never fatal to humans.

H5N1

Which of the following countries would be best to study to understand why polio has the ability to continue coming back? Nigeria Gabon Somalia Tanzania

Nigeria

Why do RNA viruses tend to have unusually high rates of mutation? RNA viruses replicate faster. RNA viruses can incorporate a variety of nonstandard bases. Replication of their genomes does not involve proofreading. RNA nucleotides are more unstable than DNA nucleotides.

Replication of their genomes does not involve proofreading.

Assuming a recent discovery is shown to be true, which of the following appears to be true? Sexual transmission of Zika can occur from a man to a woman or from a woman to a man. Sexual transmission of Zika is not possible. Sexual transmission of Zika can only occur from a man to a woman. Sexual transmission of Zika can only occur from a woman to a man.

Sexual transmission of Zika can occur from a man to a woman or from a woman to a man.

Assuming a recent discovery is shown to be true, which of the following appears to be true? Sexual transmission of Zika can only occur from a woman to a man. Sexual transmission of Zika is not possible. Sexual transmission of Zika can occur from a man to a woman or from a woman to a man. Sexual transmission of Zika can only occur from a man to a woman.

Sexual transmission of Zika can occur from a man to a woman or from a woman to a man.

When and where are new flu gene mixes most likely to emerge? Fall in North America. Winter in Asia. Summer in the Arctic. Spring in Africa.

Summer in the Arctic.

Which of the following statements correctly describes one difference between vertical and horizontal transmission of plant viruses? Vertical transmission is the spread of viruses from the upper leaves to the lower leaves of the plant, and horizontal transmission is the spread of a virus among leaves at the same general level. 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. 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. 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.

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.

How does a virus differ from a bacterium? A virus, unlike a bacterium, lacks a genome. Viruses are two-dimensional, whereas bacteria are three-dimensional. Viruses, unlike bacteria, lack metabolic enzymes.

Viruses, unlike bacteria, lack metabolic enzymes.

How does a virus differ from a bacterium? Viruses are two-dimensional, whereas bacteria are three-dimensional. A virus, unlike a bacterium, lacks a genome. Viruses, unlike bacteria, lack metabolic enzymes.

Viruses, unlike bacteria, lack metabolic enzymes.

Which of the following statements accurately describes plant virus infections? They can be controlled by the use of antibiotics. They have little effect on plant growth. They are spread via the plasmodesmata. They are rarely spread by insects.

They are spread via the plasmodesmata.

Which of the following statements accurately describes plant virus infections? They have little effect on plant growth. They can be controlled by the use of antibiotics. They are rarely spread by insects. They are spread via the plasmodesmata.

They are spread via the plasmodesmata.

How do prions differ from viruses? Unlike viruses, prions are infectious proteins. Unlike viruses, prions do not include any nucleic acids. Unlike a virus, a prion is a single molecule.

Unlike viruses, prions are infectious proteins. Unlike viruses, prions do not include any nucleic acids. Unlike a virus, a prion is a single molecule.

Why are retroviruses considered a special class of viruses? They have an RNA genome. They carry their own RNA-RNA synthesis enzymes inside their capsids. They transcribe RNA to DNA using reverse transcriptase. They leave behind mini-chromosomes when they leave a cell. They have a phospholipids membrane cloak.

They transcribe RNA to DNA using reverse transcriptase.

The H1N1 2009 outbreak is considered to have been which of the following? a pandemic a retrovirus an emerging virus an influenza of type C a virus that is found in the human species only

a pandemic

You are a doctor. A patient presents with hepatitis C. Which of the following organs is/are likely to be most affected? liver heart kidneys lungs

liver

Cycle A is the _____ cycle and cycle B is the _____ cycle. lytic ... lysogenic lytic ... phage lysogenic ... phage lysogenic ... lytic phage ... lysogenic

lytic ... lysogenic

RNA viruses require their own supply of certain enzymes because __________. these enzymes penetrate host cell membranes host cells lack enzymes that can replicate the viral genome these enzymes translate viral mRNA into proteins host cells rapidly destroy the viruses

host cells lack enzymes that can replicate the viral genome

RNA viruses require their own supply of certain enzymes because __________. these enzymes penetrate host cell membranes host cells rapidly destroy the viruses host cells lack enzymes that can replicate the viral genome these enzymes translate viral mRNA into proteins

host cells lack enzymes that can replicate the viral genome

Which of the following would currently be the most effective way to eliminate schistosomiasis in Africa? it cannot be eliminated a vaccination program deworming pill distribution prescribing all people antibiotics

deworming pill distribution

You are a genetic engineer interested in using the same technique used in this method to control the Anopheles mosquito which transmits malaria. Which of the following do you release in malaria-riddled regions? Engineered males. A random sample of engineered males and engineered females. An equal number of engineered males and engineered females. Engineered females.

engineered males

You are an epidemiologist for the Centers for Disease Control, specializing in schistosomiasis. Your goal is to reduce or eliminate this disease by focusing on the intermediate host. What are you researching? copepod black fly mosquito freshwater snail

freshwater snail

Which of the following characteristics, structures, or processes is common to both bacteria and viruses? cell division metabolism genetic material composed of nucleic acid ribosomes

genetic material composed of nucleic acid

Which of the following characteristics, structures, or processes is common to both bacteria and viruses? metabolism genetic material composed of nucleic acid cell division ribosomes

genetic material composed of nucleic acid

The pointer is indicating the virus's _____.

genome

Which of the following processes can be effective in preventing the onset of viral infection in humans? applying antiseptics taking vitamins getting vaccinated taking antibiotics

getting vaccinated

Which of the following processes can be effective in preventing the onset of viral infection in humans? taking antibiotics applying antiseptics getting vaccinated taking vitamins

getting vaccinated

Contact with which of the following is most likely to cause hepatitis C? infected saliva infected mucus infected blood infected urine

infected blood

Controlling populations of which of the following would likely cause a decline in cases of Lassa? mosquitoes bats mice blackflies

mice

Which of the following is polio best known for causing? blindness paralysis cognitive impairment internal bleeding

paralysis

Which viruses have single-stranded RNA that acts as a template for DNA synthesis? viroids proviruses retroviruses lytic phages bacteriophages

retroviruses

Which of the following characteristics determine a virus's host range? whether its nucleic acid is DNA or RNA the enzymes carried by the virus the proteins on its surface and that of the host the proteins in the host's cytoplasm

the proteins on its surface and that of the host

Viral DNA makes mRNA by the process of _____. replication infection translation lysis transcription

transcription

Based on the table, which virus meets the requirements for a bacteriophage?

A

Which of the following statements correctly describes one characteristic of the lytic cycle of viral replication? The viral genome replicates without destroying the host. Many bacterial cells containing viral DNA are produced. A large number of phages are released at a time. Viral DNA is incorporated into the host genome.

A large number of phages are released at a time.

According to the CDC regarding the recent bird flu outbreak, which of the following people should be treated with Tamiflu? Anyone who regularly eats eggs. Anyone who regularly eats chicken. A chef that cooks chicken. A trucker that transports live chickens.

A trucker that transports live chickens.

Why are viruses called obligate intracellular parasites? They must use a host cell's nucleotides for transcription and replication. They must use a host cell's amino acids to synthesize proteins. They must use a host cell's metabolic enzymes and pathways to obtain energy. They must use a host cell's ribosomes to synthesize proteins. All of the listed responses are correct.

All of the listed responses are correct.

Which of the following series of events best reflects what we know about how the flu virus moves between species? A flu virus from a human epidemic or pandemic infects birds; the birds replicate the virus differently and then pass it back to humans. An avian flu virus undergoes several mutations and rearrangements such that it is able to be transmitted to other birds and then to humans. The flu virus in a pig is mutated and replicated in alternate arrangements so that humans who eat the pig products can be infected. 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, and the virus mutates and can be transmitted to humans.

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, and the virus mutates and can be transmitted to humans.

Why is it ineffective to treat viral disease with antibiotics? Pathogenic RNA viruses have a high rate of mutation, producing new genetic varieties that are insensitive to antibiotic treatment. Due to excessive antibiotic use, most viruses have evolved to be resistant to antibiotics. Antibiotics inhibit enzymes specific to bacteria and have no effect on virally encoded enzymes.

Antibiotics inhibit enzymes specific to bacteria and have no effect on virally encoded enzymes.

In areas where schistosomiasis is rampant, having people do which of the following would be most likely to decrease the frequency of this illness? Sleep under mosquito netting. Cook their meat thoroughly. Wash their fruits and vegetables thoroughly. Avoid getting into lakes and ponds.

Avoid getting into lakes and ponds.

A person travelling to which of the following should be most concerned about contracting Zika? Africa Asia Australia Caribbean

Caribbean

A person travelling to which of the following should be most concerned about contracting Zika? Africa Caribbean Australia Asia

Caribbean

You inhale the virus for the common cold. What sentinel cells does your immune system send out to determine the location of the infection? CD4 monocytes stem cells macrophages

CD4

If using these genetically modified mosquitoes is a success, which of the following will happen in Brazil? Cases of Zika will decrease while cases of dengue fever will increase. Cases of Zika and dengue fever will increase. Cases of Zika will increase while cases of dengue fever will decrease. Cases of Zika and dengue fever will decrease.

Cases of Zika and dengue fever will decrease.

If using these genetically modified mosquitoes is a success, which of the following will happen in Brazil? Cases of Zika will increase while cases of dengue fever will decrease. Cases of Zika will decrease while cases of dengue fever will increase. Cases of Zika and dengue fever will increase. Cases of Zika and dengue fever will decrease.

Cases of Zika and dengue fever will decrease.

Your cousin is an Iowa egg producer and H5N2 is found in his flock. Which of the following will he have to do? Treat the entire flock with antivirals. Quarantine his flock for 60 days. Nothing. Destroy the entire flock.

Destroy the entire flock.

Which of the following is true? Ebola is caused by a virus, Lassa is caused by a bacterium. Ebola is caused by a bacterium, Lassa is caused by a virus. Ebola and Lassa are both caused by viruses. Ebola and Lassa are both caused by bacteria.

Ebola and Lassa are both caused by viruses.

Which of the following natural methods would likely work the best to decrease the mosquito population around your home? Do not mow your grass until it is 6 inches in height. Plant hibiscus flowers. Leave large piles of leaves lying around. Eliminate all standing water.

Eliminate all standing water.

Which of the following natural methods would likely work the best to decrease the mosquito population around your home? Plant hibiscus flowers. Do not mow your grass until it is 6 inches in height. Eliminate all standing water. Leave large piles of leaves lying around.

Eliminate all standing water.

You are a genetic engineer interested in using the same technique used in this method to control the Anopheles mosquito which transmits malaria. Which of the following do you release in malaria-riddled regions? A random sample of engineered males and engineered females. An equal number of engineered males and engineered females. Engineered males. Engineered females.

Engineered males.

Which of the following is the key to this project being a success? Following the release of the engineered mosquitoes, the offspring born in the wild will be all males. Following the release of the engineered mosquitoes, the offspring born in the wild will live, but will die before reproducing. Following the release of the engineered mosquitoes, the offspring born in the wild will live, but they will be unable to reproduce. There will be no wild offspring after the release of the engineered mosquitoes.

Following the release of the engineered mosquitoes, the offspring born in the wild will live, but will die before reproducing.

Which of the following is the key to this project being a success? Following the release of the engineered mosquitoes, the offspring born in the wild will live, but will die before reproducing. Following the release of the engineered mosquitoes, the offspring born in the wild will live, but they will be unable to reproduce. There will be no wild offspring after the release of the engineered mosquitoes. Following the release of the engineered mosquitoes, the offspring born in the wild will be all males.

Following the release of the engineered mosquitoes, the offspring born in the wild will live, but will die before reproducing.

If these mosquitoes are released in Florida and something goes wrong, which of the following agencies will be held responsible? Centers for Disease Control Food and Drug Administration United States Department of Agriculture Environmental Protection Agency

Food and Drug Administration

If these mosquitoes are released in Florida and something goes wrong, which of the following agencies will be held responsible? Environmental Protection Agency Food and Drug Administration United States Department of Agriculture Centers for Disease Control

Food and Drug Administration

Which of the following is most similar to the agent that causes hepatitis C? Ringworm, caused by a fungus. A strep infection caused by a bacterium. Schistosomiasis, caused by a protozoan parasite. HIV, caused by a virus.

HIV, caused by a virus.

Somalia wants to emulate Egypt's hepatitis C treatment program. Which of the following would be best for them to do? Have patients pay whatever they can. Have doctors set drug prices. Have pharmacists set drug prices. Have the government set official drug prices.

Have the government set official drug prices.

You are an epidemiologist. You wish to visit the origin of the H5N1 that is frequently in the headlines. Where should you go? Moscow Hong Kong Johannesburg Chicago

Hong Kong

Which of the three types of viruses shown in the figure would you expect to include glycoproteins as part of their overall structure? Which of the three types of viruses shown in the figure would you expect to include glycoproteins as part of their overall structure? I only II only III only I and II only

I and II only

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 If you already knew that the infectious agent was either bacterial or viral, which treatment would allow you to distinguish between these two possibilities? I II III IV either II or IV

III

Your aunt likely came in contact with hepatitis C while in Egypt 7 years ago. Which of the following is true? If she had contracted hepatitis C, she would have died by now. If she had contracted hepatitis C, she may not be symptomatic yet. If she had contracted hepatitis C, she would have active symptoms by now. If she had contracted hepatitis C, she would be at the end stage of the disease by now.

If she had contracted hepatitis C, she may not be symptomatic yet.

Which of the following is currently a problem regarding Zika? It is unknown as to how long Zika can survive in semen. There is no test for Zika in semen. The semen test for Zika is unreliable, with numerous false positives and false negatives. Semen can only be tested for Zika after a man is infected for six months.

It is unknown as to how long Zika can survive in semen.

Which of the following is currently a problem regarding Zika? There is no test for Zika in semen. It is unknown as to how long Zika can survive in semen. The semen test for Zika is unreliable, with numerous false positives and false negatives. Semen can only be tested for Zika after a man is infected for six months.

It is unknown as to how long Zika can survive in semen.

What happens first when a phage infects a bacterial cell and is going to enter a lysogenic cycle? The host cell is lysed by the invasion. All bacterial descendants will carry the viral genes. When the bacterial chromosome replicates, viral DNA is also replicated. Linear DNA circularizes. Viral DNA becomes inserted into the bacterial chromosome.

Linear DNA circularizes.

Based on what happened in Nigeria, what is most likely to occur in Sierra Leone? Over time, the LARGE mutation will disappear from the population. Over time, the number of people with the LARGE mutation will increase. Over time, the number of people with the LARGE mutation will decrease to about 5% of the population. Over time, the number of people with the LARGE mutation will stay about the same.

Over time, the number of people with the LARGE mutation will increase.

Where are doctors most likely to find new polio patients to treat? Turkey Kenya Egypt Pakistan

Pakistan

In 2009, a flu pandemic was believed to have originated when viral transmission occurred from pig to human, thereby earning the designation, "swine flu." Although pigs are thought to have been the breeding ground for the 2009 virus, sequences from bird, pig, and human viruses were all found within this newly identified virus. What is the most likely explanation of why this virus contained sequences from bird, pig, and human viruses? Related viruses can undergo genetic recombination if the RNA genomes mix and match during viral assembly. The virus was descended from a common ancestor of bird, pig, and human flu viruses. The human was likely infected with various bacterial strains that contained all three RNA viruses. The infected individuals happened to be infected with all three virus types.

Related viruses can undergo genetic recombination if the RNA genomes mix and match during viral assembly.

You work for the World Health Organization and are sent to the last known place where polio was found in Africa to help ensure it does not return. Where do you go? Nigeria Somalia Gabon Tanzania

Somalia

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 __________. T2 protein and T2 DNA T4 protein and T2 DNA T4 protein and T4 DNA T2 protein and T4 DNA

T4 protein and T4 DNA

Which of the following statements correctly describes the most probable fate of a newly emerging virus that causes high mortality in its host? The new virus replicates quickly and undergoes rapid adaptation to a series of divergent hosts. The newly emerging virus will die out rather quickly or will mutate to be far less lethal. It is able to spread to a large number of new hosts quickly because the new hosts have no immunological memory of them. Sporadic outbreaks will be followed almost immediately by a widespread pandemic.

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

Which of the following statements correctly describes the most probable fate of a newly emerging virus that causes high mortality in its host? The newly emerging virus will die out rather quickly or will mutate to be far less lethal. Sporadic outbreaks will be followed almost immediately by a widespread pandemic. It is able to spread to a large number of new hosts quickly because the new hosts have no immunological memory of them. The new virus replicates quickly and undergoes rapid adaptation to a series of divergent hosts.

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

Which of the following statements correctly describes the lysogenic cycle of lambda (λ) phage? Most of the prophage genes are activated by the product of a particular prophage gene. Certain environmental triggers can cause the phage to exit the host genome, switching from the lytic to the lysogenic. The phage genome replicates along with the host genome. After infection, the viral genes immediately turn the host cell into a lambda-producing factory, and the host cell then lyses.

The phage genome replicates along with the host genome.

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? The plants would develop symptoms typically produced by viroids. The plants would develop some but not all of the symptoms of the TMV infection. The plants would not show any disease symptoms. The plants would develop the typical symptoms of TMV infection.

The plants would develop the typical symptoms of TMV infection.

Evidence suggests that factors which contribute towards the virulence of E. coli strain O157:H7, a bacterial strain reported to cause several food poisoning deaths, are caused by genes from a virus that infects bacteria. Considering this evidence, which statement most likely explains how the O157:H7 population acquired the genetic variation that distinguishes the strain from harmless E. coli strains, such as those that reside in our intestines? Viral envelope proteins bind to receptors on the bacterial membrane, allowing the viral genetic material to enter the bacterium and become translated into proteins. The virus infected the bacterium, and allowed the bacterial population to replicate with a copy of the phage genome in each new bacterium. The virus entered the bacterial cell and incorporated its DNA into the bacterial genome, allowing the bacteria's cellular machinery to create new viruses. The virus entered the cell and acquired specific genes from the bacteria to increase the virulence of the virus.

The virus infected the bacterium, and allowed the bacterial population to replicate with a copy of the phage genome in each new bacterium.

If Zika follows recent trends of the top three sexually transmitted diseases in the United States, which of the following will happen? There will be a decrease in the number of Zika cases resulting from sexual contact. There will be an increase in the number of Zika cases resulting from sexual contact. There will be an increase in the number of Zika cases in men resulting from sexual contact, but a decrease in the number of women contracting Zika from sexual contact. There will be no change in the number of Zika cases resulting from sexual contact.

There will be an increase in the number of Zika cases resulting from sexual contact.

If Zika follows recent trends of the top three sexually transmitted diseases in the United States, which of the following will happen? There will be an increase in the number of Zika cases in men resulting from sexual contact, but a decrease in the number of women contracting Zika from sexual contact. There will be a decrease in the number of Zika cases resulting from sexual contact. There will be an increase in the number of Zika cases resulting from sexual contact. There will be no change in the number of Zika cases resulting from sexual contact.

There will be an increase in the number of Zika cases resulting from sexual contact.

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

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

Which of the following statements correctly describes the best predictor of how much damage a virus causes? whether the viral mRNA can be transcribed ability of the infected cell to undergo normal cell division whether the infected cell produces viral protein ability of the infected cell to carry on translation

ability of the infected cell to undergo normal cell division

A human pandemic is __________. a virus that increases in mortality rate as it spreads a flu that kills more than 1 million people a viral disease that infects all humans an epidemic that extends around the world

an epidemic that extends around the world

The herpesviruses 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 virus (HSV) types I and II, causing facial and genital lesions, and the varicella zoster virus (VSV), causing chicken pox and shingles. Each of these three actively infects 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. In order to be able to remain latent in an infected live cell, HSV must be able to shut down what process? all immune responses apoptosis of a virally infected cell DNA replication transcription of viral genes

apoptosis of a virally infected cell

The herpesviruses 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 virus (HSV) types I and II, causing facial and genital lesions, and the varicella zoster virus (VSV), causing chicken pox and shingles. Each of these three actively infects 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. In order to be able to remain latent in an infected live cell, HSV must be able to shut down what process? apoptosis of a virally infected cell transcription of viral genes DNA replication all immune responses

apoptosis of a virally infected cell

Which of the following is why someone who has had a herpesvirus-mediated cold sore or genital sore may have flare-ups for the rest of his or her life? co-infection with an unrelated virus that causes the same symptoms re-infection by the same herpesvirus strain re-infection by a closely related herpesvirus of a different strain copies of the herpesvirus genome remaining as mini-chromosomes in some host cell nuclei

copies of the herpesvirus genome remaining as mini-chromosomes in some host cell nuclei

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, 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. Treat the substance with nucleases that destroy all nucleic acids and then determine whether it is still infectious. II. Filter the substance to remove all elements smaller than what can be easily seen under a light microscope. III. Culture the substance by itself on nutritive medium, away from any plant cells. IV. Treat the sample with proteases that digest all proteins and then determine whether it is still infectious. If you already knew that the infectious agent was a prion, which treatment would allow you to distinguish this? I only II only III only IV only either I or IV

either I or IV

The herpesviruses 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 virus (HSV) types I and II, causing facial and genital lesions, and the varicella zoster virus (VSV), causing chicken pox and shingles. Each of these three actively infects 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. 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? medication that destroys surface HSV before it gets to neurons treatment of the HSV lesions to shorten the breakout interference with new viral replication in preexisting cases vaccination of all persons with preexisting cases

interference with new viral replication in preexisting cases

You are a genetic engineer working to control Zika by altering the organism that transmits it. Which of the following are you working on? mosquitoes spiders blackflies bees

mosquitoes

You are a genetic engineer working to control Zika by altering the organism that transmits it. Which of the following are you working on? bees mosquitoes blackflies spiders

mosquitos

In the figure, when new viruses are being assembled (IV), what mediates the assembly? host cell chaperones assembly proteins coded for by the viral genes assembly proteins coded for by the host nucleus nothing; the proteins self-assemble

nothing; the proteins self-assemble

What is a virus that attacks a bacterium? viroid retrovirus prion phage paramyxovirus

phage

HIV uses which of the following processes to synthesize a DNA strand using its RNA genome as a template? conjugation translation transcription reverse transcription reverse translation

reverse transcription

Which of the following responses correctly lists the order of events in a generalized viral replicative cycle? the virus enters the cell, host enzymes replicate the viral genome, enzymes transcribe the viral genome into mRNA host enzymes replicate the viral genome, enzymes transcribe the viral genome into mRNA, the virus enters the cell enzymes transcribe the viral genome into mRNA, the virus enters the cell, host enzymes replicate the viral genome the virus enters the cell, enzymes transcribe the viral genome into mRNA, host enzymes replicate the viral genome

the virus enters the cell, host enzymes replicate the viral genome, enzymes transcribe the viral genome into mRNA

Which of the following is key to eradicating polio? clean drinking water mosquito control adequate Vitamin C vaccinations

vaccinations

In the lysogenic cycle _____. host DNA is destroyed and viral DNA is replicated a bacterium replicates without passing viral DNA to its daughter cells viral DNA is destroyed and host DNA is replicated a bacterium divides once before the lytic cycle is initiated viral DNA is replicated along with host DNA

viral DNA is replicated along with host DNA


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