Question 1

The alpha coronaviruses infect the same tissue type although the host range may differ.

Accepted Answer

The answer of The alpha coronaviruses infect the same tissue...

Question 2

Small infectious RNA molecules that are able to cause disease in plants are called ________.

Accepted Answer

The answer of Small infectious RNA molecules that are able...

Question 3

All viruses require host cell enzymes for translation.

Accepted Answer

Viruses lack the machinery to carry out protein synthesis on their own, so they rely on the host cell's enzymes and ribosomes for translation.

Question 4

A bigger discrepancy between direct count and PFU estimates of virion numbers might be expected for influenza virus than for herpes virus.

Accepted Answer

Influenza virus particles have a filamentous or pleomorphic morphology, and may form aggregates, which can make their direct counting difficult. On the other hand, herpes virus particles are generally more uniform in shape and size, making their direct counting more reliable. Therefore, there may be a larger discrepancy between the direct count and PFU estimates for influenza virus compared to herpes virus.

Question 5

Filtration of a bacteriophage preparation replicated in E.coli will effectively separate viable cells from phage particles.

Accepted Answer

Filtration can effectively separate bacteriophage particles from E. coli cells because phages are much smaller than bacterial cells, allowing them to pass through filters that retain the larger cells.

Question 6

A bacterial strain that contains a phage genome integrated into its chromosome is called a _________.

Accepted Answer

The answer of A bacterial strain that contains a phage...

Question 7

Proto-oncogenes never play a necessary role in development and growth of an organism.

Accepted Answer

Proto-oncogenes are actually necessary for the normal growth and development of an organism. They are responsible for promoting growth and division of cells, and they only become problematic when they are mutated or activated inappropriately, leading to uncontrolled cell growth and potentially leading to cancer.

Question 8

Enveloped viruses acquire their envelope from host cell membranes.

Accepted Answer

Enveloped viruses have a lipid membrane envelope that surrounds their nucleocapsid. This envelope is acquired from the host cell membrane during the process of viral budding. The envelope contains glycoprotein spikes that are used for viral attachment and entry into host cells.

Question 9

Viruses categorized in the same Baltimore group may possess common proteins.

Accepted Answer

Baltimore classification is based on the type of nucleic acid in the virus and the replication strategy they use. Viruses in the same Baltimore group have some common features in their replication strategy and may have similar proteins involved in their replication cycle.

Question 10

The zone of clearing as a result of a phage infection on a lawn of E.coli growing on the surface of an agar plate is called a ________.

Accepted Answer

The answer of The zone of clearing as a result...

Question 11

Genes that are involved in the normal regulation of the cell cycle and can be altered to increase probability of cancer are called ___________.

Accepted Answer

The answer of Genes that are involved in the normal...

Question 12

Which characteristics are found in viroids? (Select all that apply)

Accepted Answer

The answer of Which characteristics are found in viroids? (Select...

Question 13

A virus which can selectively kill cancerous cells can be termed: (Select all that apply)

Accepted Answer

The answer of A virus which can selectively kill cancerous...

Quiz 5: Viruses