Understanding Viruses

These vocabulary flashcards cover key concepts and terminology related to viruses, their structure, replication, classification, and effects on host organisms.

Virus

A small acellular particle that can infect living cells, containing either DNA or RNA.

Obligate Intracellular Parasite

A virus that can only reproduce inside a host cell.

Virology

The study of viruses, their properties, and their effects on living organisms.

Electron Microscope

An instrument that uses electrons to visualize small structures, such as viruses.

Heredity

The transmission of genetic characteristics from parents to offspring.

Viral Replication

The process by which a virus reproduces within a host cell.

Capsid

The protein shell that encloses the viral genome.

Enveloped Virus

A virus with an outer lipid membrane derived from the host cell.

Naked Virus

A virus without a lipid envelope.

Bacteriophage

A virus that infects bacteria.

Lytic Cycle

A viral reproductive cycle resulting in the destruction of the host cell.

Lysogenic Cycle

A viral cycle where the viral DNA integrates into the host genome without causing lysis.

Induction

The process by which a lysogenic bacteriophage switches to the lytic cycle.

Host Range

The spectrum of hosts that a virus can infect.

Tissue Tropism

The preference of a virus for specific cell types within a host.

Genome

The complete set of genetic material of an organism.

RNA Polymerase

An enzyme that synthesizes RNA from a DNA template.

Reverse Transcriptase

An enzyme used by retroviruses to convert RNA into DNA.

Budding

The process by which enveloped viruses exit a host cell.

Parvovirus

The smallest known virus, measuring around 20 nm in diameter.

Viral Envelope

A lipid layer surrounding some types of viruses, aiding in infection.

Virus-First Hypothesis

The theory that viruses may have existed before cellular life forms.

Progressive Hypothesis

The theory that viruses originated from mobile genetic elements escaping cells.

Regressive Hypothesis

The idea that viruses evolved from once free-living cells that became parasitic.

Capsomere

A protein subunit that makes up the viral capsid.

Epidemiology

The study of how diseases spread and can be controlled.

Viroid

A small infectious agent composed of RNA, without a protein coat.

Plasmid

A small, circular piece of DNA that can replicate independently of chromosomal DNA.

Transposon

A mobile genetic element that can move within a genome.

Morphology

The physical structure and shape of a virus.

Spikes

Protein structures on the surface of a virus that facilitate attachment to host cells.

Viral Infection

The assimilation and replication of a virus within a host organism.

Cell Lysis

The destruction of a cell by a virus leading to the release of new viral particles.

Temperate Phage

A bacteriophage that can enter the lysogenic cycle.

Cryogenic Preservation

A method that can be used to preserve viral samples by freezing.

Genetic Material

The DNA or RNA that contains the information for viral replication.

Horizontal Gene Transfer

The movement of genetic material between organisms through non-reproductive ways.

Lysogenic Conversion

The acquisition of new traits by a bacterium through interaction with a temperate phage.

Virulence Factor

A component that enhances a pathogen's ability to cause disease.

Host Cell Receptor

Specific proteins on the surface of host cells that viruses bind to for entry.

Fecal–Oral Route

Common pathway for transmission of certain viruses, often involving contaminated food or water.

Nucleocapsid

The combination of nucleic acid and protein in a virus.

Viral Assembly

The process where viral components come together to form complete virus particles.

Mosaic Genome

A viral genome that contains both viral and host-derived sequences.

Pathogenicity

The ability of an organism, such as a virus, to cause disease.

Antiviral Drug

A medication used to treat viral infections by inhibiting viral replication.

Viral Transmission

The spread of viruses from one host to another.

Quarantine

An enforced isolation to control the spread of viral diseases.

Infection Cycle

The various stages a virus goes through while replicating within a host.