Viral Infection

Flashcards covering key concepts related to viral infections and their characteristics.

What is a virus?

A non-living particle that depends on a host to reproduce.

Why are viruses considered nonliving?

They do not exhibit all the characteristics of living things.

Examples of viral diseases

Measles, Covid, Mumps, Chicken pox, Influenza, Herpes.

What is the suspected origin of viruses?

Evidence suggests that viruses came from parts of cells, as the genetic material of viruses is similar to cell genes.

Rank from smallest to largest: virus, prokaryotic cell, eukaryotic cell.

Virus, prokaryotic cell, eukaryotic cell.

What is the outer layer of a virus called?

The capsid, which is made of proteins.

What is a bacteriophage?

A virus that infects bacteria.

What does a virus require in order to reproduce?

It needs to attach to a host cell.

What happens during the lytic cycle?

The virus takes over the cell's DNA to make viral DNA and the cell bursts, releasing new viruses.

What does 'lyse' mean?

The cell bursts.

Active virus examples in the short cycle

Common cold and influenza.

What is the lysogenic cycle?

The injected DNA integrates itself into the chromosomes of the host cell, and during reproduction, each new cell contains the viral DNA.

What are latent (passive) virus examples?

Herpes and HIV, which may remain dormant for years.

How long does the lytic infection cycle take to show symptoms?

Symptoms appear in 1-4 days.