Cheat Sheet 10: Understanding Viruses

Virus

Non-living infectious particle that replicates inside cells.

Bacteriophage

Virus that infects bacterial cells.

Retrovirus

RNA virus using reverse transcriptase for DNA synthesis.

Epidemic

Disease outbreak in a large population.

Pandemic

Global spread of a disease.

Acute Infection

Rapid onset, brief symptoms, resolves in days.

Chronic Infection

Long-lasting infection with low viral load.

Latent Infection

Intermittent high and low viral loads over years.

Nucleic Acid

Viral genome, can be RNA or DNA.

Antigenic Shift

Gene mixing increases host range and treatment difficulty.

Antigenic Drift

Minor genetic changes in viruses over time.

Prophage

Viral genome integrated into bacterial genome.

Provirus

Viral genome integrated into eukaryotic genome.

Capsid

Protein coat protecting viral nucleic acid.

Viral Envelope

Outer membrane layer from host cell membranes.

CRISPR-Cas System

Bacterial defense mechanism cutting viral genomes.

Prions

Infectious misfolded proteins causing other proteins to misfold.

Viroids

Single-stranded RNA molecules that infect plants.

Lytic Cycle

Active viral replication leading to host cell destruction.

Lysogenic Cycle

Viral genome integrates into host genome passively. Can turn Lytic

Attachment

Initial binding of virus to host cell.

Entry

Virus genome enters host cell.

Uncoating

Viral capsid breakdown exposing viral genome.

Synthesis/Replication

Virus replicates genome using host's resources.

Self-assembly

Viral components spontaneously form new viral particles.

Release

New viral particles exit host cell.

Viral Load

Amount of virus present in the body.

Viral Shedding

Release of virus from infected host.

Viral Glycoproteins

Proteins on viral envelope aiding in infection.

Host Range

Set of species a virus can infect.

Restriction Enzymes

Cut viral DNA to prevent replication.

Viral Outbreaks

Sudden increase in virus infections.

Viruses and bacteria both have this:

Nucleic Acids