chapter 16 questions

cancer can develop from exposure to human papillomavirus (HPV).

Cervical

All viruses contain genetic material, which is either RNA or ______, and a(n) ______ coat that surrounds the genetic material.

DNA; protein

True or False: The nucleic acids of viruses acquire mutations that can be passed on to new viruses inside a host cell.

True

Viruses that infect bacteria are called

bacteriophages

Vaccination for HPV in both girls and boys before they are sexually active helps prevent HPV-associated

cancers.

Select all of the ways that prions can be transmitted or acquired by humans.

cannibalism tainted biological materials used in medical procedures occur spontaneously inherited

Viroids cause severe disease in many types of

crop plants.

Influenza viruses infect cells lining the airways of the respiratory system, and as a result ______ build up in the airways.

dead and damaged cells

Using antibiotics to treat viral infections is ill-advised, because their use selects for ______, a growing public health problem.

drug-resistant bacteria

Medical scientists have created ______ that help fight against viral infections by targeting viral proteins, but despite this many viruses remain incurable.

drugs

Some viruses have an outer lipid-rich ______ that surrounds the protein coat.

envelope

A virus is an infectious agent that consists of

genetic information surrounded by a protein coat.

During the penetration stage of viral infection,

genetic material of the virus enters the cell.

Cold sores on the lips of humans may indicate a latent infection of

herpes simplex I.

The most virulent viruses

kill the host.

A(n) ______ is an infectious protein and is simpler than a virus.

prion

Diseases called spongiform encephalopathies are caused by ______ and affect the ______, which becomes riddled with holes.

prions; brain

The term prion is an abbreviation that stands for

proteinaceous infectious particle.

The capsid is a coating that surrounds the DNA or RNA of a virus. Capsids are composed of what type of organic molecule?

proteins

From the choices below, select the types of cells that can be infected with viruses.

protists fungi plants bacteria animals

What HIV enzyme transcribes the viral RNA into DNA, which can then integrate into host T cell genome?

reverse transcriptase

Select all the viruses for which successful vaccines have been created.

smallpox mumps

Mutations in the viral genome can occur during what stage in viral replication in which multiple copies of the viral genome are made?

synthesis

Preventative treatments for viruses called ______ cause the immune system to recognize molecular components of a virus without exposing the person to the disease, conferring future immunity to the target virus.

vaccines

Attachment, penetration, synthesis, assembly, and release are the stages of

viral replication.

A(n) ______ is a tightly wound circle of RNA without a protein coat that can infect a plant cell.

viroid

The ability of a virus to damage its host during an infection is termed

virulence.

Natural selection acts on viruses because

viruses have nucleic acids, which undergo mutations

Bacteriophages are ______ that infect ______ cells.

viruses; bacterial

How does an abnormal prion protein (PrP) form?

contact with an abnormal PrP

What symptom of influenza infection is due to dead and damaged host cells in the airway?

cough and sore throat

Select all of the following that are true about the human immunodeficiency virus (HIV).

has an RNA genome is an enveloped virus can cause latent infections contains the enzyme reverse transcriptase

What feature of a host cell determines whether a particular virus can infect that type of cell?

presence of specific receptors on the host cell surface

Select all of the following that are true about the viral envelope.

present in HIV contains embedded proteins composed of lipids derived from host cell membrane

What infectious particle can be encoded by a gene, which can be transmitted to offspring?

prion

What is the name for a protein that exists in several three-dimensional shapes, and one of those shapes can cause a disease?

prion

A particular type of virus can only enter a cell that has the correct

receptors on its surface

The ______ of a virus is the host that acts as a continual source of the virus.

reservoir

A host organism that carries a virus and may or may not show symptoms of an infection is called a

reservoir.

Select all of the types of genetic material that can be found in different types of viruses.

single-stranded RNA double-stranded RNA double-stranded DNA single-stranded DNA

Although they do not have cell components such as cytoplasm or ribosomes, some ____ have enzymes and lipid-rich envelopes.

viruses

Select all of the following that are true about the human immunodeficiency virus (HIV)

can cause latent infections is an enveloped virus contains the enzyme reverse transcriptase has an RNA genome

The time between initial infection by a virus and host cell death

can vary between less than an hour to many years.

Latent viruses, such as human papillomavirus and Epstein-Barr virus, can induce a cell division disorder called ______ because they are signaling the host cell to continue to divide.

cancer

All viruses have a(n) ______, which is the protein coat that surrounds a virus. Multiple choice question.

capsid

What happens when an abnormal prion protein (PrP) contacts a normal PrP, and a chain reaction of protein refolding is triggered?

Masses of abnormal PrPs accumulate in cells.

A ______ is a noncellular, small, infectious agent that is simply genetic information enclosed in a protein coat.

virus

How do abnormal prion proteins cause disease?

Masses of abnormal prions cause brain cells to die.

What disease results when HIV causes such an immense loss of T cells that the body's immune system is defenseless against infections and cancer?

AIDS

Select all the ways that the development of cervical cancer can be prevented or greatly reduced.

Get the HPV vaccine before becoming sexually active. Limit the number of sexual partners. Use condoms during sexual intercourse.

What virus is responsible for the disease AIDS?

HIV

Select all of the following that are true of HIV in a latent infection.

HIV's genetic information remains dormant. HIV genes are integrated into the host cell's DNA.

True of false: Treatments that are effective against viruses and bacteria can also be used to destroy prions.

False

What type of HIV treatment would prevent HIV from entering host cells?

Fuzcon, which blocks host cell receptors

What is the best method to ensure that prions are not transmitted to humans other than by inheritance?

Keep brains and spinal cord tissue out of food and medical products.

Select all the ways in which anti-HIV medications slow the replication of HIV.

They block the reverse transcriptase enzyme. They inhibit assembly of new viruses inside host cells. They block molecules that HIV uses to enter cells. They inhibit viral DNA integration into host DNA.

What is one reason that most biologists do not consider viruses to be alive?

They cannot reproduce on their own.

Select all the reasons that viruses are not considered alive.

Viruses do not metabolize. Viruses do not respond to stimuli.

Viruses can infect

all species.

Anti-HIV drugs are more effective at treating HIV when

an active infection is occurring.

The genetic variability of viruses complicates the development of ______ drugs.

antiviral

Select all of the types of cancer that can be caused by human papillomavirus (HPV).

anus throat penis vagina cervix

The ______ range of a virus is all the kinds of organisms or cells that it can infect.

host

What virus can cause cervical cancer?

human papillomavirus

Select all of the types of latent viruses that can lead to cancer because they persist by signaling the host cells to divide continuously.

human papillomavirus Epstein-Barr virus

According to the Investigating Life essay and the image, HIV-1 groups M, N, and O have

independent origins.

How does a viroid cause infection in plants?

interferes with protein production in host cells

In viruses with an envelope, proteins in the envelope help the virus

invade or attach to a new host cell.

All viruses contain genetic material surrounded by a protein coat. In addition, some viruses have other features. Select all the features from the list below that some viruses have.

lipid-rich envelope enzymes

The outer envelope present in some viruses, such as the influenza virus and the human immunodeficiency virus (HIV), is composed of ______, which may be derived from the host cell's membrane.

lipids

The high ______ rate of flu viruses makes it difficult to produce influenza vaccines that are effective against all strains.

mutation

A viroid is

naked RNA that can infect plant cells.

Cancer can be caused by a latent virus because

the latent virus is signaling the host cell to continue to divide.

The host range of a virus is

the range of organisms or cells that the virus can infect.

A latent viral infection is one in which

the viral genetic information remains inside the cell but does not cause disease symptoms.

Review the Investigating Life essay. Select all of the following that researchers have discovered about SIV and HIV-1.

They encode similar amino acids. They have genetic similarities.

In viruses, the DNA or RNA

can be either single-stranded or double-stranded.

Antibiotics are targeted to the cell walls and enzymes of ______, and they are not effective against ______.

bacteria; viruses

Select all the diseases that are caused by prions.

kuru "mad cow disease" Creutzfeldt-Jakob disease spongiform encephalopathies

A ______ infection of an animal virus does not produce disease symptoms or new viruses, but the viral information remains inside the cell.

latent

When a virus infects a cell, from where does the virus get ATP, tRNA, nucleotides, ribosomes, and amino acids required for the production of new viral nucleic acid and viral proteins?

the host cell

Vaccines work by causing

the immune system to recognize molecular components of the virus without the person having the disease.

In the production of the influenza vaccine, ______ are often used to provide cells and raw materials.

fertilized chicken eggs

Select all of the following that are shapes found in different types of viruses.

filamentous spherical icosahedral

What features do all viruses have?

genetic material and a capsid