Review Questions

Which statement is true?

1. A virion contains DNA and RNA.
2. Viruses are acellular.
3. Viruses replicate outside of the cell.
4. Most viruses are easily visualized with a light microscope.

The viral ________ plays a role in attaching a virion to the host cell.

1. core
2. capsid
3. envelope
4. both b and c

Viruses_______.

1. all have a round shape
2. cannot have a long shape
3. do not maintain any shape
4. vary in shape

Which statement is not true of viral replication?

1. A lysogenic cycle kills the host cell.
2. There are six basic steps in the viral replication cycle.
3. Viral replication does not affect host cell function.
4. Newly released virions can infect adjacent cells.

Which statement is true of viral replication?

1. In the process of apoptosis, the cell survives.
2. During attachment, the virus attaches at specific sites on the cell surface.
3. The viral capsid helps the host cell produce more copies of the viral genome.
4. mRNA works outside of the host cell to produce enzymes and proteins.

Which statement is true of reverse transcriptase?

1. It is a nucleic acid.
2. It infects cells.
3. It transcribes RNA to make DNA.
4. It is a lipid.

Oncogenic virus cores can be_______.

1. RNA
2. DNA
3. neither RNA nor DNA
4. either RNA or DNA

Which is true of DNA viruses?

1. They use the host cell’s machinery to produce new copies of their genome.
2. They all have envelopes.
3. They are the only kind of viruses that can cause cancer.
4. They are not important plant pathogens.

A bacteriophage can infect ________.

1. the lungs
2. viruses
3. prions
4. bacteria

Which of the following is NOT used to treat active viral disease?

1. vaccines
2. antiviral drugs
3. antibiotics
4. phage therapy

Vaccines_______.

1. are similar to viroids
2. are only needed once
3. kill viruses
4. stimulate an immune response

Which of the following is not associated with prions?

1. replicating shapes
2. mad cow disease
3. DNA
4. toxic proteins

Which statement is true of viroids?

1. They are single-stranded RNA particles.
2. They reproduce only outside of the cell.
3. They produce proteins.
4. They affect both plants and animals.