Viruses, Viroids, and Prions

These flashcards consist of key vocabulary terms and definitions based on the biology of viruses, viroids, and prions as covered in the microbiology lecture notes.

Virus

An obligate intracellular parasite that requires a living host cell to multiply and contains genetic material (DNA or RNA) and a protein coat.

Bacteriophage

A type of virus that specifically infects bacteria.

Virion

A complete, fully developed viral particle composed of nucleic acid and a protein coat.

Capsid

The protein coat that surrounds and protects the viral nucleic acid.

Envelope

A lipid, protein, and carbohydrate coating on some viruses.

Lytic cycle

A type of viral multiplication that results in the lysis and death of the host cell.

Lysogenic cycle

A type of viral multiplication where the viral DNA is incorporated into the host DNA without destroying the host cell.

Plaques

Clear areas on a plate of live bacteria that indicate bacterial lysis caused by bacteriophages.

Phage conversion

The process in which lysogenic bacteria exhibit new properties due to the incorporation of phage DNA.

Oncogenes

Genes that can transform normal cells into cancerous cells.

Viroid

A short piece of naked RNA that causes disease in plants.

Prion

Infectious protein particles that can cause neurodegenerative diseases.

Cytopathic effect

The observable damage to host cells as a result of viral infection.

Antibody tests

Diagnostic tests that detect the presence of antibodies against viruses, such as Western blot.

Nucleic acid testing

Techniques such as PCR that identify the presence of viral genetic material in a sample.

Animal viruses

Viruses that specifically infect animals; categorized by the type of nucleic acid they contain.

Persistent viral infection

A type of viral infection characterized by the continuous release of viruses over time.

Latent viral infection

Infection where the virus remains dormant within the host cells and can reactivate later.