Viruses - replication Flashcards
What type of cells do viruses need to reproduce?
Living cells, referred to as host cells
Viruses are parasitic and cannot replicate independently.
List the steps required for viral replication.
- Attach to a specific attachment site on the host cell
- Inject their nucleic acid into the cytoplasm
- Use the host cell’s machinery to produce viral proteins
- Assemble new viral particles
- Release the new viral particles from the host cell
These steps are essential for all viruses to replicate.
What is the lytic pathway?
A viral replication process where new virus particles are released during lysis of the host cell
Named for the bursting of the host cell.
What enzyme causes lysis in the lytic pathway?
Lysozyme
This enzyme is coded for by the virus’s genetic material.
What are fully functional virus particles called?
Virions
These are produced before the host cell undergoes lysis.
Describe the first step of the lytic pathway.
The virus attaches to the cell membrane of the host cell using attachment proteins
This is crucial for the infection process.
What occurs during the biosynthesis step of the lytic pathway?
The virus uses proteins and enzymes within the host cell to produce new virus particles
This step is essential for creating new virions.
What happens to the host cell at the end of the lytic cycle?
The host cell undergoes lysis, releasing virions into the host organism
This allows the virus to infect more cells.
What is a key difference between the lytic pathway and the lysogenic pathway?
In the lysogenic pathway, new virus particles are not immediately released and do not immediately cause disease
This leads to a dormant state of the viral nucleic acid.
What is latency in the lysogenic pathway?
The period during which viral nucleic acid combines with the host DNA and is not transcribed or translated
This allows the host cell to function normally.
What can trigger a lytic event in the lysogenic pathway?
Changes in the cell’s environment, such as exposure to UV rays and certain chemicals
These changes can activate the dormant viral DNA.
What is the time during which latency occurs called?
Period of lysogeny
During this time, the host cell continues normal functions.
Fill in the blank: Viruses use the _______ of their host cell to produce viral proteins.
protein synthesis machinery
This is critical for the replication process.
When do viruses undergo the lysogenic pathway?
Inbetween reproductive cycles
