Micro Chapter 13

Question 1

What is a virion?

Answer 1

fully developed infectious particle

Question 2

What composes a Virus?

Answer 2

• Genome (Usually DNA)

- B Capsid/Coat

Question 3

What is different about the genetic material in HIV?

Answer 3

RNA not DNA

Question 4

Describe a virus’s coat

Answer 4

• unique

- used for identification

Question 5

Describe a virus’s envelope

Answer 5

• composed of protein, phospholipids, and carbs

- made from small piece of host cell’s plasma membrane

Question 6

What are virus spikes?

Answer 6

entry (hemaglutination) and exit (neuraminidase) mechanisms

Question 7

In a virus name, what do the numbers represent? For example in H1N1

Answer 7

• number of changes in spike protein

- Hem group and neuraminidase went through one change each

Question 8

What two types of spikes does HIV have?

Answer 8

1. GP41

2. GP120

Question 9

Describe an HIV virion

Answer 9

• can move around
• two RNA strands
• capsid
• spikes
• enzyme reverse transcription

Question 10

Why is HIV called a retrovirus?

Answer 10

because of reverse transcription

Question 11

Describe reverse transcription

Answer 11

1. RNA converted to single strand DNA through use of RT enzyme
2. New DNA replicated through use of RT enzyme
3. Viral DNA penetrates nucleus of host and inserts into existing DNA to create a provirus to continue infection

Question 12

What is a latent provirus?

Answer 12

provirus is dormant (asymptomatic) for a period of time

Question 13

An HIV provirus can…

Answer 13

completely change a host cell into a cancer cell called Kaposis Sarcoma (effects blood vessels and skin cells)

Question 14

Why is the development of a vaccine so hard for HIV?

Answer 14

• mutates almost every time reverse transcription occurs

Question 15

What cell is most vulnerable to HIV?

Answer 15

CD4

Question 16

3 Stages of CDC

Answer 16

1. CD4 500mm3- lymphadenopathy
2. CD4 200-499mm3- fever, diarrhea, shingles, hairy leukoplakia, cervix is precancerous
3. CD4- clinical stag, pneumonia. brain degeneration, vision loss (sarcoma)

Question 17

HIV is transmitted mostly through

Answer 17

• semen and vaginal secretions

Question 18

While saliva contains HIV there is less risk of transmission because…

Answer 18

there are way fewer HIV particles

Question 19

What is the Cytopathic Effect?

Answer 19

structural changes in host cell due to viral invasion

1. Lytic Infection
2. Persistant Infection
3. Latent Infection
4. Cancer

Question 20

Describe a Lytic Infection

Answer 20

• acute

- destroys host cell

Question 21

What is an example of a lytic infection?

Answer 21

influenza

Question 22

What is a Persistent Infection?

Answer 22

• does not kill cell

Question 23

What is an example of a Persistent Infection?

Answer 23

• measles can cause brain degeneration and death

- Rubella

Question 24

What is an example of a Latent Infection?

Answer 24

• Shingles (Herpes-3)

- Cold Sores (Herpes-1)

Question 25

What are two types of Cancer that demonstrate cytopathic effect?

Answer 25

1. Burkits Lymphoma- tumor of jaw caused by Herpes-4

2. Nasopharyngeal