Viral replication in host cells

Overview

Outline what happens when a bacteriophage infects a bacterium and consequence for the patient of HIV destroying helper T-cells.

What you need to know

Answer each one before you reveal it.

Questions from this subtopic

Each one with the model answer underneath.

1. 1

   Why can a virus only replicate inside a living cell?

   Model answer

   A virus has no ribosomes, enzymes or energy supply of its own, so it must use the metabolic machinery of a host cell to make new virus particles.

2. 2

   What happens to a host cell as new virus particles are produced within it?

   Model answer

   The cell is destroyed as the newly made virus particles are released from it.

3. 3

   Which group of organisms do bacteriophages infect?

   Model answer

   Bacteriophages infect bacteria.

4. 4

   Describe in outline what happens when a bacteriophage infects a bacterium.

   Model answer

   The phage invades the bacterial cell, replicates inside it using the bacterium's machinery, and the bacterial cell is destroyed as new phages are released.

5. 5

   Suggest why a bacteriophage cannot infect a human cell.

   Model answer

   Its attachment proteins are complementary only to receptor molecules on the bacterial surface, which human cells do not carry.

6. 6

   Which type of human cell does HIV invade?

   Model answer

   HIV invades helper T-cells, a type of lymphocyte.

Other ways to work this

The same content, four other ways.

What is inside Levo

Six ways to work the same material.