Chapter 20 Viruses Part 1

Question 1

What is a virus? Describe its basic structure.

Answer 1

nonliving particle made of proteins, nucleic acids, and sometimes lipids

Question 2

what surrounds all viruses and what is it made of

Answer 2

capsids, protein coats

Question 3

what does a virus have inside that has the instructions for making copies of the virus

Answer 3

RNA OR DNA

Question 4

True or False - Viruses only come in THREE shapes and sizes, and TWO structures

Answer 4

False - MANY, MANY

Question 5

What is on the outside of a virus that acts as identifiers?

Answer 5

Proteins

Question 6

What do specific proteins on the outside of a virus do? Why do they do this?

Answer 6

they bind to specific receptors on the cells surface - they act as identifiers so that they can do this

Question 7

most viruses infect a __________ cell

Answer 7

specific

Question 8

what are viruses that only infect bacteria called

Answer 8

bacteriophages

Question 9

why are viruses not living?

Answer 9

they cannot reproduce on their own

Question 10

what are the two types of viral infections

Answer 10

lytic and lysogenic

Question 11

what does it mean to lyse a cell

Answer 11

the cells bursts open releasing the virus particles

Question 12

which of the two viruses automatically begins chopping up the host cell’s DNA

Answer 12

lytic infection

Question 13

Which viral infection never leaves your body? Why?

Answer 13

Lysogenic infection bc the cell copies its DNA and viral material for generations

Question 14

What is a prophage?

Answer 14

host and viral DNA combined together

Question 15

What are the two ways that viruses cause disease?

Answer 15

they destroy living cells and upset homeostasis by affecting cellular processes

Question 16

insert a bacteriophage - label the head, tail fibers, sheath, DNA

Answer 16

They are ALL CAPSIDS

Question 17

ESSAY AND “SHORT ANSWER”: What are two ways that we can PREVENT viruses? Explain both in detail.

Answer 17

One way in which you can prevent viruses is with an injection of a vaccine. This helps to build up immunity because it injects a weakened virus or a similar but less dangerous pathogen. Washing your hands is another great way to prevent a virus. If done well, this practice dislodges viruses or bacteria from your hands so that you don’t spread them to other parts of your body as well.

Question 18

What treatments do we have for viruses? Explain what is used and what they do.

Answer 18

Anti-viral drugs treat viruses because they stop activation by attacking specific viral enzymes that the host cell doesn’t have, to speed recovery or stop activation. An example of an anti-viral drug is tamiflu. This anti-viral works by attacking the flu virus to keep it from multiplying in your body and by reducing symptoms of the flu.

Question 19

What does a virus have to have to survive? Why?

Answer 19

Viruses have to have living cells in order to survive. Outside of a body, they cannot survive because the capsids will begin to degrade and the likelihood of it surviving decreases rapidly.

Question 20

Be able to explain how you know the difference in a lytic virus and a lysogenic virus.

Answer 20

The lytic cycle involves the reproduction of viruses using a host cell to manufacture more viruses; the viruses then burst out of the cell. The lysogenic cycle involves the incorporation of the viral genome into the host cell genome, infecting it from within.

Question 21

THE LYTIC AND LYSOGENIC CYCLE OF BATERIOPHAGES IS YOUR TITLE FOR THE DIAGRAM - study over the diagram like crazy bc there is a lot of things on it and i cannot type them all on here

Answer 21

try to memorize most of it or at least key words