Deck 15: Viruses

Question 1

The stage of viral replication in which the virus binds a cell surface receptor is:

A)Release
B)Penetration
C)Synthesis
D)Attachment
E)Assembly

Answer 1

D

Question 2

HIV is a:

A)Double-stranded DNA virus
B)Single-stranded RNA virus
C)Single-stranded DNA virus
D)Double-stranded RNA virus
E)Prion

Answer 2

B

Question 3

Viruses:

A)Consist of only a single cell
B)Are smaller than cells
C)Consist of multiple cells
D)Contain a nucleus
E)Contain ribosomes

Answer 3

B

Question 4

The type of viral infection in which a virus enters a host cell and then remains dormant (hidden)in a host cell's chromosome is:

A)A rare form of viral infection
B)A transgenic infection
C)A lytic infection
D)A systematic infection
E)A lysogenic infection

Question 5

A layer of host cell membrane attached to a virus is called:

A)An envelope
B)A protein coat
C)A capsomere
D)A capsid
E)A plasmid

Question 6

A capsid is:

A)A lipid coat of a virus
B)A viral DNA molecule
C)A protein coat of a virus
D)A viral RNA molecule
E)The area in the virus where its genetic information is located

Question 7

The stage of viral replication in which the host cell produces viral nucleic acids and proteins is:

A)Release
B)Attachment
C)Synthesis
D)Penetration
E)Assembly

Question 8

Which of the following diseases is NOT caused by viruses?

A)The common cold and influenza
B)Smallpox and mononucleosis
C)Polio and rabies
D)Aids and warts
E)Diabetes

Question 9

Most viruses:

A)Infect only a few closely related species
B)Only infect animal cells
C)Infect a wide variety of organisms
D)Cannot infect living cells
E)Only infect plant cells

Question 10

The shape of a virus is determined by:

A)Its DNA
B)Its RNA
C)Its envelope
D)Its host
E)Its coat protein organization

Question 11

Viruses that infect bacteria are:

A)Not known to exist
B)Prions
C)Bacteriophages
D)Composed of protein only
E)Also capable of causing disease in humans

Question 12

The stage of viral replication in which the new viruses leave the host cell is:

A)Release
B)Attachment
C)Penetration
D)Synthesis
E)Assembly

Question 13

The host range of a virus is:

A)The geographical location in which the virus is found
B)The type of organisms or cells that a virus can infect
C)Determined by receptor molecules on living cells
D)Determined by the prey it feeds on
E)The biome it is found in

Question 14

The treating of a viral infection by inoculating the host with a bacterial virus:

A)Is chemotherapy
B)Is phage therapy
C)Is radiation therapy
D)Is antibiotic therapy
E)None of these are correct

Question 15

The influenza viruses that infect man usually are derived from a type that could also infect:

A)Horses and sheep
B)Cattle and water buffalo
C)Chimpanzees and gorillas
D)Birds and pigs
E)A variety of primates

Question 16

The stage of viral replication in which viral components are put together to form new viruses is:

A)Release
B)Assembly
C)Attachment
D)Penetration
E)Synthesis

Question 17

The type of viral infection in which a virus enters a host cell immediately replicates and causes the host cell to burst is:

A)A rare form of viral infection
B)A transgenic infection
C)A lysogenic infection
D)A lytic infection
E)A systematic infection

Question 18

The stage of viral replication in which the viral nucleic acid is released inside the cell is:

A)Penetration
B)Release
C)Attachment
D)Synthesis
E)Assembly

Question 19

The correct sequence of the stages of viral replication is:

A)Attachment - Synthesis - Penetration - Assembly - Release
B)Penetration - Attachment - Assembly - Synthesis - Release
C)Penetration - Attachment - Synthesis - Release - Assembly
D)Attachment - Penetration - Assembly - Synthesis - Release
E)Attachment - Penetration - Synthesis - Assembly - Release

Question 20

The genetic information in viruses:

A)Is found in the nucleus of the virus
B)Is always DNA
C)Can be DNA or RNA
D)Is always RNA
E)Can be replicated outside of a cell

Question 21

Viral DNA inserted into a chromosome of the host is:

A)A carrier
B)A phage
C)A reservoir
D)A prophage
E)A lytic infection

Question 22

Viruses are not considered to be alive,yet they share this ability with living cells:

A)They can metabolize food
B)They can evolve
C)They can reproduce on their own
D)They can produce cell membranes
E)They can synthesize proteins

Question 23

Oral infections with herpes simplex virus 1 can lie dormant in nerve cells for years,and when a patient becomes stressed,the virus is released,forming cold sores on the lips.Why would the virus form a cold sore?

A)To allow it to spread to a new host
B)So that it can mutate and survive an antibiotic treatments
C)To move to another part of the body
D)To avoid the immune system
E)To warn other people that the host is infected

Question 24

An infectious RNA molecule is a:

A)Virus
B)Virion
C)Viroid
D)Prion
E)Prophage

Question 25

Drugs like Aziodothymidine (AZT):

A)Inhibit viral DNA from inserting into the host chromosome
B)Inhibit the cleaving of proteins needed to make the protein coat of a virus
C)Inhibit host cells from reproducing
D)Inhibit reverse transcriptase
E)Inhibit viruses from entering a host cell

Question 26

Our most potent weapon in the fight against viruses is:

A)Antibiotics
B)Sulfa drugs
C)Gene therapy
D)Surgery
E)Vaccinations

Question 27

Since viruses have no active methods of entering plant cells,they must rely upon mechanically caused wounds,vegetative propagation of plants,grafting,seed,pollen,and being carried on the mouth parts of chewing insects.Tobacco mosaic virus is most commonly introduced into plants through small wounds caused by handling and by insects chewing on plant parts.What would prevent viruses from easily entering plant cells?

A)The cell wall on the virus
B)The plasma membrane on the plant
C)The cell wall on the plant
D)The plasma membrane on the virus
E)The protein coat on the virus

Question 28

HIV:

A)Is a retrovirus
B)Infects most mammals
C)Can be killed with antibiotics
D)Causes liver cancer
E)Can be transmitted through the skin

Question 29

The Human Immunodeficiency Virus (HIV)only affects a specific class of cells in the immune system called T helper cells,and not other types of T cells.Which is the best explanation for this observation?

A)HIV can only replicate inside of T helper cells
B)Only T helper cells have reverse transcriptase
C)The T helper cells are not necessary for the immune system to fight viral infections
D)Only T helper cells have the correct receptor on their cell surface
E)HIV can only be released from T helper cells

Question 30

The enzyme that HIV uses to convert its RNA into DNA is:

A)Reverse transcriptase
B)DNA polymerase
C)RNA polymerase
D)RNA integrase
E)Transcriptase

Question 31

Oral infections with herpes simplex virus 1 can lie dormant in nerve cells for years,and when a patient becomes stressed,the virus is released,forming cold sores on the lips.Where will the virus be while dormant in the nerve cell?

A)Floating in the nerve cell cytoplasm
B)Integrated in the nerve cell chromosomes
C)In the nerve cell membrane
D)Floating outside of the nerve cell, waiting to reinfect it
E)In the blood

Question 32

Oral infections with herpes simplex virus 1 can lie dormant in nerve cells for years,and when a patient becomes stressed,the virus is released,forming cold sores on the lips.In a cold sore,the virus is in which of the following states?

A)Latent
B)Lysogenic
C)Assembly
D)Remissive
E)Asymptomatic

Question 33

An infectious protein is a:

A)Virus
B)Viroid
C)Prion
D)Virion
E)Prophage

Question 34

Many doctors recommend that all women be vaccinated for HPV before they become sexually active.Which step in the viral life cycle would first be blocked by a vaccine?

A)Attachment
B)Penetration
C)Synthesis
D)Assembly
E)Release

Question 35

Hepatitis A and C contain an RNA genome while hepatitis B contains a DNA genome.What could you conclude about these hepatitis viruses?

A)They do not all share a common ancestor
B)They do not all affect the liver
C)They all have the same symptoms
D)They all have the same mode of transmission
E)They all have the same rate of occurrence

Question 36

Human Papilloma Virus (HPV)can be transmitted sexually,and causes genital warts and cervical cancer.Why might a virus trigger increased cell growth?

A)To use the cell's mitochondria to perform respiration
B)Viruses are parasites and can only grow on dead cells
C)To protect the virus from the immune system
D)To allow the virus to spread to other people
E)To use the cell's replication machinery to make more virus

Question 37

A patient receiving a protease inhibitor and AZT is probably being treated for an infection by:

A)A bacterium
B)A protozoan
C)A DNA virus
D)A retrovirus
E)A fungus

Question 38

A reason or reasons given by scientists as to why viruses are not considered living organisms include:

A)Viruses do not contain genetic information
B)Viruses do not reproduce on their own
C)Viruses are all smaller than the smallest known cells
D)Viruses do not contain a nucleus
E)Viruses can be frozen and still survive

Question 39

Most antibiotics are not effective against viruses because these antibiotics do which of the following?

A)Inhibit synthesis of cell walls
B)Destroy DNA and RNA
C)Inhibit all protein synthesis
D)Target capsids
E)Inhibit reverse transcriptase

Question 40

Oral infections with herpes simplex virus 1 can lie dormant in nerve cells for years,and when a patient becomes stressed,the virus is released,forming cold sores on the lips.While lying dormant the virus is in which of the following states?

A)Lysogenic
B)Symptomatic
C)Latent
D)Replicative
E)Infective

Question 41

Given the structure of the anti-HIV drug azidothymidine (AZT),how do you think it blocks viral replication?

A)It blocks RNA synthesis
B)It inhibits host T cells from replicating
C)It inhibits the assembly of new viruses in the cell
D)It blocks DNA synthesis
E)It prevents HIV from entering the cell

Question 42

Viruses always lack which of the following?

A)A plasma membrane
B)Genetic material
C)A protein coat
D)Organelles

Question 43

The vaccine against the influenza virus is prepared by treating the virus with detergent.How would this inactivate the virus?

A)By destroying the envelope
B)By destroying the protein coat
C)By destroying the RNA
D)By destroying the DNA
E)By inhibiting viral assembly

Question 44

The influenza virus contains an RNA genome.Every year the common flu vaccine is designed to protect against three different strains of the influenza virus.Why do scientists typically have to make a new vaccine every year?

A)Because our bodies develop resistance to the vaccine and it becomes less effective
B)Because the virus develops resistance to the vaccine
C)Because the virus can mutate into new strains
D)Because people change their habits each year and become susceptible to different strains of the virus
E)Because the common influenza virus can come from many species of animals including cats and dogs

Question 45

Rhinovirus is an RNA virus that causes the common cold and sinus infections.The virus does not contain an envelope.Which of the following is true of a rhinovirus?

A)It does not contain protein or genetic material
B)It does not contain genetic material
C)It does not contain protein
D)It does not contain lipid or protein
E)It does not contain lipid

Question 46

What is the genetic material found in HIV?

A)Protein
B)RNA
C)DNA
D)Lipid
E)Carbohydrate

Question 47

Viruses can infect all higher life forms such as plants and animals,but cannot infect bacteria.

Question 48

figure 15.4
Reviewing figure 15.4,which of the following is true of HIV?

A)It contains DNA as its genetic material
B)It replicates in the cytoplasm of cells
C)It lyses cells when it is released
D)It uses reverse transcriptase from the cell to make DNA
E)It is an enveloped virus

Question 49

Poliomyelitis is an RNA virus that can invade the nervous system and cause paralysis within a matter of hours.Polio has been virtually eliminated world-wide by which of the following?

A)Antibiotics
B)Vaccination
C)Mosquito control
D)Quarantine
E)Improve water quality

Question 50

figure 15.4
SIV causes symptomless infections in monkeys and apes,yet causes AIDS-like disease in chimpanzees.HIV is closely related to SIV and causes AIDS in humans.Which of the following is the best explanation for these observations?

A)Monkeys, apes, and chimpanzees are all genetically very similar
B)The effects of viruses on different species is random
C)Chimpanzees and humans have a more recent common ancestor
D)SIV is most likely lytic in apes and monkeys
E)SIV is most likely latent in chimpanzees

Question 51

How did the researchers first know that Marilyn the chimp may be infected with HIV?

A)Because she had HIV RNA in her blood
B)Because she had HIV DNA in her tissues
C)Because she had been used in HIV research
D)Because she had raised antibodies against HIV
E)Because she had symptoms of HIV infection, or AIDS

Question 52

Many viruses are inhibited by antibiotics.

Question 53

Smallpox is an enveloped virus with a DNA genome.We have eliminated this once deadly virus through an aggressive world-wide vaccination program.Why might a vaccine be successful with smallpox,but not with HIV?

A)Because smallpox is an enveloped virus
B)Because viruses with DNA genomes must replicate inside a host cell
C)Because RNA is more stable than DNA, and is less likely to be destroyed by the vaccine
D)Because host cells have RNA in them, and thus don't raise antibodies against RNA
E)Because DNA genomes mutate less rapidly than RNA genomes

Question 54

figure 15.9
It has been difficult to generate drugs to treat AIDS for which reason?

A)HIV does not cause AIDS
B)HIV does not use any enzymes that can be targeted by drugs
C)HIV mutates rapidly because reverse transcriptase lacks proofreading
D)The only way to kill a virus is with a vaccine, not with drugs
E)People with HIV infections die very rapidly, before the drugs have a chance to cure them

Question 55

figure 15.9
If a person is treated with a single anti-HIV drug,they often end up with a resistant strain.How does this occur?

A)The drugs weaken the immune system, making a patient more susceptible to infection with resistant strains of HIV
B)The drug causes mutations in the HIV, making them resistant to the drug
C)The drugs kill all sensitive viruses, leaving only the pre-existing resistant viruses
D)The HIV wants to avoid the drug, so it becomes resistant

Question 56

figure 15.9
Based on figure 15.9,which of the following statements is most likely accurate?

A)HIV arose more than once
B)HIV groups M, N, and O will be more similar to each other than to SIV
C)SIV only arose once
D)The SIV strains will all have more sequence similarity with each other than with any of the HIV groups
E)HIV and SIV are not genetically related

Question 57

figure 15.4
Reviewing figure 15.4,why could researchers use PCR to amplify viral DNA from the chimp Marilyn's tissues?

A)Because the HIV is converted to DNA and integrated into a cell's chromosome
B)Because PCR uses a reverse transcriptase and can thus detect RNA
C)Because HIV uses DNA as its genetic material
D)Because some of the HIV will be stuck to the outside of a cell
E)Because PCR can amplify any genetic material

Question 58

Rhinovirus is an RNA virus that causes the common cold and sinus infections.The virus does not contain an envelope.What would you predict to be the primary route of transmission of rhinovirus?

A)Sexual contact
B)Blood
C)Aerosol
D)Insects
E)Parasites

Question 59

Most scientific evidence points to the HIV viruses originating in Africa.

Question 60

A vaccine against the influenza virus would result in production of antibodies against which of the following?

A)The protein coat
B)Viral RNA
C)Viral DNA
D)Proteins in the envelope
E)Lipids in the envelope