Infectious Disease

Question 1

A disease caused by the virus variola.

Answer 1

Small pox

Question 2

A small, infectious agent composed of genomic material and a protein shell.

Answer 2

A virus

Question 3

What is an icosohedron?

Answer 3

A 20-facet structure containing 12 vertices. This is the shape taken by virus capsids.

Question 4

The process by which a virus recognizes and begins to interact with cell surface protein receptors.

Answer 4

Attachment

Question 5

What is viral penetration?

Answer 5

The process by which viruses enter into a host cell.

Question 6

What is uncoating?

Answer 6

The process by which viruses shed the capsid proteins so that the genome may begin generating proteins and start replicating inside the hose cell.

Question 7

What is viral assembly?

Answer 7

The process of generating new virions inside an infected cell. This requires new genomes of the virus being folded into the capsid proteins.

Question 8

The part of the virus life cycle where no infectious virus can be extracted from cells which have just been exposed to infectious virions.

Answer 8

Eclipse Phase

Question 9

What is viral transformation?

Answer 9

The process by which the host cell becomes immortalized and potentially cancerous as a result of virus infection.

Question 10

What is a viral vector?

Answer 10

An organism, often an invertebrate arthropod, that transmits a virus from one animal (reservoir) to another (the host).

Question 11

What are the phases of viral replication?

Answer 11

1. Attachment
2. Penetration
3. Uncoating
4. Synthesis, translation
5. Replication
6. Assembly
7. Budding or lysis from host cell

Question 12

What is latency?

Answer 12

When a virus infects a host cell and becomes quiescent with little-to-no genomic replication or protein production. It is through latency that some viruses can transform host cells resulting in immortalization and the development of monoclonal cancer production.

Question 13

What is necessary for viral replication?

Answer 13

The genome of a virus can be DNA or RNA, can be single or double stranded. All viruses must make a single-stranded positive sense RNA in order to translate proteins and replicate.

Question 14

What is tropism?

Answer 14

Determines what host cells a virus can infect and is determined by cell surface receptors and the viral surface glycoproteins.

Question 15

What kinds of variability is seen in viral disease?

Answer 15

• Acute and self-limited
• Acute with novel disease manifestations much later after the infection
• Persistent in the host, but latent with occasional reactivation
• Chronic infection with constant manifestations of disease or manifestations of disease much later

Question 16

Why are viruses obligate intracellular parasites?

Answer 16

Without a host cell they are incapable of any metabolic activity.