Virus - Wikipedia
WEBA virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity.
Introduction to viruses - Wikipedia
WEBA virus is a tiny infectious agent that reproduces inside the cells of living hosts. When infected, the host cell is forced to rapidly produce thousands of identical copies of the original virus. Unlike most living things, viruses do not have cells that divide; new viruses assemble in the infected host cell.
Viral disease - Wikipedia
WEBA viral disease (or viral infection) occurs when an organism's body is invaded by pathogenic viruses, and infectious virus particles (virions) attach to and enter susceptible cells. Examples are the common cold, gastroenteritis and pneumonia.
Virus - Simple English Wikipedia, the free encyclopedia
WEBViruses are a strand of nucleic acid with a protein coat. Usually the nucleic acid is RNA; sometimes it is DNA. Viruses cause many types of diseases, such as polio, ebola and hepatitis. Viruses reproduce by getting their nucleic acid strand into a …
Virus | Definition, Structure, & Facts | Britannica
WEBApr 12, 2024 · Virus, infectious agent of small size and simple composition that can multiply only in living cells of animals, plants, or bacteria. Viruses possess unique infective properties and thus often cause disease in host organisms. Learn about the history, types, and features of viruses.
Intro to viruses (article) | Viruses | Khan Academy
WEBKey points: A virus is an infectious particle that reproduces by "commandeering" a host cell and using its machinery to make more viruses. A virus is made up of a DNA or RNA genome inside a protein shell called a capsid. Some viruses have an external membrane envelope. Viruses are very diverse.
Viruses - National Geographic Society
WEBOct 19, 2023 · noun. pathogenic agent that lives and multiplies in a living cell. Viruses are tiny infectious agents that invade host cells and cause disease. Although they are harmful, viruses also have interesting technological potential.
Virus facts and information - National Geographic
WEBFeb 22, 2019 · Inside their cellular hosts, viruses can create an enormous number of copies and spread the infection to other cells. For example, if you get the flu, your body will be riddled with some hundred ...
Viruses: Definition, Types, Characteristics & Facts - Cleveland Clinic
WEBMar 29, 2023 · Viruses are small germs (pathogens) that can infect you and make you sick. They can infect humans, plants, animals, bacteria and fungi. Each one infects only specific types of hosts. Viral infections in humans can cause no symptoms or make you extremely ill. Types of diseases they can cause include:
Viruses: Definition, Structure, Classification - PMC
WEBAbstract. Viruses are infectious units with diameters of about 16 nm (circoviruses) to over 300 nm (poxviruses; Table 2.1). Their small size makes them ultrafilterable, i.e. they are not retained by bacteria-proof filters. Viruses have evolved over millions of years, and have adapted to specific organisms or their cells.
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