Who knows at this point - VIRUSES

What is a virus?

A pathogen that causes disease by infecting cells.

Are viruses considered alive by themselves?

No, viruses are not alive by themselves.

What are viruses made of?

DNA or RNA inside a protein coat called a capsid. Some also have a membrane.

How do viruses reproduce?

They hijack a host cell's metabolism and force it to make more virus particles.

What happens when a cell produces too many viruses?

The cell may burst, or lyse.

What are bacterial viruses called?

Bacteriophages (phages).

What occurs during the lytic cycle?

The virus immediately directs the cell to make many new phages.

What happens to the host cell in the lytic cycle?

The cell bursts (lyses), releasing new viruses.

What occurs during the lysogenic cycle?

Viral DNA inserts into the host chromosome and remains dormant.

What can happen after a lysogenic cycle?

The virus can become active and enter the lytic cycle.

Which common virus behaves similarly to a lytic phage?

The influenza (flu) virus.

Why is HIV similar to a lysogenic phage?

HIV inserts its genetic material into the human genome

What body system can destroy virus particles?

The immune system

Why don't antibiotics work against viruses?

Viruses are not alive, so antibiotics cannot target them.

How do most antiviral treatments work?

They target viral proteins involved in replication to reduce the number of virus particles; HIV treatment often uses a drug "cocktail" of multiple medications.