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Virus

Definition(s)

Minute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.

Definition from: MeSH via Unified Medical Language SystemThis link leads to a site outside Genetics Home Reference. at the National Library of Medicine

A microorganism that can infect cells and cause disease.

Definition from:  National Cancer Institute dictionaryThis link leads to a site outside Genetics Home Reference.

A virus is an infectious agent that occupies a place near the boundary between the living and the nonliving. It is a particle much smaller than a bacterial cell, consisting of a small genome of either DNA or RNA surrounded by a protein coat. Viruses enter host cells and hijack the enzymes and materials of the host cells to make more copies of themselves. Viruses cause a wide variety of diseases in plants and animals, including AIDS, measles, smallpox, and polio.

Definition from: Talking Glossary of Genetic TermsThis link leads to a site outside Genetics Home Reference. from the National Human Genome Research Institute

Related discussion in the Handbook

See also Understanding Medical Terminology.

 
Published: December 16, 2014