Acellular Infectious Agents (Viruses, Viroids, and Prions)

These flashcards cover key terms and concepts about acellular infectious agents, specifically viruses, viroids, and prions, based on the lecture notes.

Virus

An acellular infectious agent that cannot replicate without a host cell.

Capsid

A protein coat that encloses the nucleic acid of a virus.

Nucleocapsid

The complete form of a virus particle consisting of a nucleic acid and its protein coat.

Host range

The number of different host cells that a virus can infect.

Virion

The complete, infective form of a virus outside a host cell.

Lytic cycle

A viral replication process that immediately replicates in a host cell and leads to the lysis of the host cell.

Lysogenic cycle

A viral replication cycle in which the viral genome integrates into the host genome and replicates silently.

Transduction

The process by which bacterial DNA is transferred from one bacterium to another by a virus.

Viroids

Infectious agents composed solely of circular RNA without a protein coat, infecting plants.

Prions

Infectious proteins that cause disease by misfolding normal proteins in host organisms.

Endocytosis

The process by which a virus is engulfed by a host cell.

Membrane fusion

A method by which enveloped viruses enter host cells by fusing their envelope with the host cell membrane.

Acute infection

A rapid onset infection with a short duration, typically resulting in the death of the host cells.

Persistent infection

A long-lasting viral infection where the virus remains in the host cells for extended periods.

Budding

The process wherein enveloped viruses exit the host cell by acquiring a portion of the host cell membrane.

Cytopathic effects (CPEs)

Virus-induced damage to host cells that alters their appearance and function.

Genomic reassortment

The mixing of genetic material from different strains of viruses within a host cell.

Reverse transcriptase

An enzyme used by retroviruses to convert RNA into DNA.

Oncoviruses

Viruses that can cause cancer by integrating their genome into host cell DNA, often leading to uncontrolled cell growth.