Chapter 33 Part 2:

Question 1

T/F the interaction between viruses and their host cells are very specific?

Answer 1

T, some component of the outer covering of the virus that recognizes a particular molecule in the surface in of the host cell.

Question 2

Describe the specific interaction that takes place between HIV cells and CD4?

Answer 2

• HIV is an enveloped protein that interacts very specifically with a protein called CD4.
  CD4, which interacts on the subset of immune cells, in particular helper T-cells.
• This interaction is what gives HIV the ability to bind to helper T-cells.
  ( 1st step in getting it getting the virus into the cell is the initial binding that occurs.)

Question 3

Describe the steps involved with getting a virus into the cell

Answer 3

• Bind to the specific external receptor that is key for getting molecules into the cell.
• Enter the host and go through the process of uncoding.

Question 4

What is the process of uncoding?

prokaryotes

Answer 4

• free up the viral genome so it can be used up within the host cell.

Question 5

Describe the interactions of bacterial phages and how this relates to them getting into the cell?

Answer 5

• each type of phage has very specific tail fibers that allow it to find a specific kind of bacterial cell
  ( 1st step in getting it getting the virus into the cell is the initial binding that occurs.)
  ——————————————————————————
• ## drills a cell wall through the cell wall and membrane , and injects its genome into the cell.-Then the genome is uncoded and can be utilized by the host cell genome.

Question 6

Describe the process of uncoding in eukaryotes. use the HIV example used in lecture?
(enveloped viruses that bind to the cellular receptor)

Answer 6

• enveloped vires will dock onto the surface of the host cell.
• causing a shape change in the receptor, which brings the bacteria closer to host. Then the plasma membrane simply fuses to the envelope of the virus.
• Then the viral capsid slides into the host cell and once inside the capsid proteins dissociate and now the viral genome is free.

Question 7

Describe the process of uncoding in eukaryotes?

all non-enveloped viruses, and some enveloped viruses

Answer 7

• The binding of that cell to the surface of that cells receptor tricks it into bringing it into the cell via endocytosis.
• begins the process of converting an endosome into a lysosome as the pH drops, which causes a shape change in some of the viral proteins
• Such that, the virus then fuses with the endosome and releases its contents into the endosome.