Compare and contrast a provirus and viral DNA. (1 point)

Question

• A provirus is bacterial DNA incorporated into the viral DNA.
• A provirus is the host cell's DNA that has been destroyed.
• A provirus is newly replicated viral DNA after injection.
• A provirus is viral DNA incorporated into the host cell's DNA.

Answer 1

The correct statement is: A provirus is viral DNA incorporated into the host cell's DNA.

Comparison:

1. Nature:

   • Provirus: It is a form of viral DNA that becomes integrated into the genome of a host cell.
   • Viral DNA: This refers to the genetic material of a virus that can exist independently before it interacts with a host cell.

2. Function:

   • Provirus: Once integrated, it can be replicated along with the host's DNA and may remain dormant for long periods, potentially leading to the production of new viral particles when activated.
   • Viral DNA: It is typically the active form that directs the machinery of the host to produce new viral components and can cause immediate infection.

Contrast:

• Integration:

  • Provirus: Specifically describes the integrated state within the host genome.
  • Viral DNA: Can exist in both integrated or free (episomal) forms but does not necessarily imply integration into the host's DNA.

• Relationship to Host:

  • Provirus: Represents a latent phase where the viral material can influence the host's cellular functions without causing immediate lytic effects.
  • Viral DNA: Generally indicates an active infection phase, leading to the production of new viruses and potentially resulting in cell lysis.

In summary, a provirus is specifically the viral DNA integrated into the host cell's DNA, whereas viral DNA can refer to both integrated and non-integrated forms of viral genetic material present in the host.