Virology 1.A

Question 1

What are the three critical things a virus needs? What is one optional thing a virus may have/need?

Answer 1

A virus must have:

1. ) A genome which determines how will proceed in infecting the host/ producing proteins
2. ) A capsid which is typically protein in origin that protects the genome.
3. ) A receptor/ligand interaction, which determines which cell-type a virus can interact and effect (Lock and Key)

Optional:
Envelope (typically developed after a lytic event from dead/remaining viral particles)

Question 2

What are the 4 types of viral genomes?

Answer 2

1. ) Single-Stranded DNA (ssDNA)
2. ) Double-Stranded DNA (dsDNA)
3. ) Single-Stranded RNA (ssRNA)
4. ) Double-Stranded RNA (dsRNA)

Question 3

5 steps of viral replication in a “nutshell”

Answer 3

1. ) Attachment (adsorption)
2. ) Penetration (Injection)
3. ) Synthesis of nucleic acid and protein
4. ) Assembly and packaging
5. ) Release (lysis)

Question 4

Why do viruses have a “co-evolution” with their host? Why is receptor-ligand binding so important?

Answer 4

Viruses have to evolve at the perfect co-evolution with the host. Too little evolution and proliferation will result in ineffective infection, more importantly too much will kill the host which in turn kills the virus. Receptor ligand binding is so important because then the virus matches perfect.

These things are Called specificity.

Question 5

What is the standard viral pathway?

Answer 5

Lytic infection in which integration and replication is immediate resulting in multiple viral progeny and spread of the virus.

Envelopes are produced by lytic leftover material.

Question 6

Example of Lytic Infection?

Answer 6

Rotavirus

Rotavirus is a genus of double-stranded RNA viruses in the family Reoviridae.

Question 7

What does a virus release into a host cell?

Answer 7

Nucleic acids (DNA or RNA)

Question 8

How does viral nucleic acids replicate in a host cell?

Answer 8

Utilizing the host cell machinery

Question 9

What is “budding”

Answer 9

Budding ultimately results in pinching off of the virion from the host membrane, thereby releasing the virus into the extracellular space. Some viruses bud at the plasma membrane (PM), whereas others are assembled at intracellular membranes along the secretory pathway.

Question 9

What is “budding”

Answer 9

Budding ultimately results in pinching off of the virion from the host membrane, thereby releasing the virus into the extracellular space. Some viruses bud at the plasma membrane (PM), whereas others are assembled at intracellular membranes along the secretory pathway.

Question 10

What is Viral latency, and what part of the viral life cycle does it relate too?

Answer 10

Viral latency is the ability of a virus to lay dormant in a cell, denoted as the lysogenic part of the life cycle.

Question 11

What can push viruses into lytic phases from lysogenic phases?

Answer 11

Stress, immuno-compromisation, etc.

Question 12

Two examples of Dormant viruses in latency

Answer 12

HIV, Herpes Zoster (VZV)

Question 13

Difference between antiviral therapies and antibiotic therapies with target specificity?

Answer 13

Antivirals are very virus specific! Whereas antibiotics are attack the cell wall of bacteria (which all have) so most antibiotics are effective for a wide range.

Question 14

What is Tamil used for? How?

Answer 14

Used again Influenza.

Neuraminidase inhibitor-horses with viral release from cells.

Question 14

What is Tamil used for? How?

Answer 14

Used again Influenza.

Neuraminidase inhibitor-horses with viral release from cells.