A virus is a biological agent that reproduces inside the cells of living hosts. When infected, a host cell is forced to produce many thousands of identical copies of the original virus, at an extraordinary rate. Unlike most living things, viruses do not have cells that divide; new viruses are assembled in the infected host cell. Over 2,000 species of viruses have been discovered. A virus consists of two or three parts: genes, made from either DNA or RNA, long molecules that carry the genetic information; a protein coat that protects the genes; and in some, an envelope of fat that surrounds and protects them when they are not contained within a host cell. Viruses vary in shape from the simple helical and icosahedral to more complex structures. They spread in many different ways. Whereas viruses such as influenza are spread through the air by people when they cough or sneeze, others such as norovirus, which are transmitted by the faecal-oral route, contaminate hands, food and water. Rotavirus is often spread by direct contact with infected children. The human immunodeficiency virus, HIV, is one of several major viruses that are transmitted during sex. Viral infections often cause disease in humans and animals; however, they are usually eliminated by the immune system, conferring lifetime immunity to the host for that virus.
Read more: https://en.wikipedia.org/wiki/Introduction_to_viruses
_______________________________ Today's selected anniversaries:
1520:
The islands of Saint Pierre and Miquelon (modern city of Saint- Pierre pictured) were discovered by Portuguese explorer João Álvares Fagundes near Canada, who named them "Islands of the 11,000 Virgins". https://en.wikipedia.org/wiki/Saint_Pierre_and_Miquelon
1854:
Florence Nightingale and a staff of 38 nurses were sent to Turkey to help treat wounded British soldiers fighting in the Crimean War. https://en.wikipedia.org/wiki/Florence_Nightingale
1867:
The first of the Medicine Lodge Treaties was signed between the United States and several Native American tribes in the Great Plains, requiring them to relocate to areas in present-day western Oklahoma. https://en.wikipedia.org/wiki/Medicine_Lodge_Treaty
1950:
Korean War: British and Australian troops of the 27th British Commonwealth Brigade engaged in heavy fighting with North Korean forces in the Battle of Yongju. https://en.wikipedia.org/wiki/Battle_of_Yongju
1987:
Sri Lankan Civil War: Indian Army soldiers, belonging to the Indian Peace Keeping Force, entered the Jaffna Teaching Hospital in Jaffna, Sri Lanka, and began killing about 68–70 patients, nurses, doctors and other staff members. https://en.wikipedia.org/wiki/Jaffna_hospital_massacre
_____________________________ Wiktionary's word of the day:
gleek: 1. (archaic) To jest, ridicule, or mock; to make sport of. 2. (informal) To discharge a thin stream of liquid through the teeth or from under the tongue. https://en.wiktionary.org/wiki/gleek
___________________________ Wikiquote quote of the day:
To love for the sake of being loved is human, but to love for the sake of loving is angelic. --Alphonse de Lamartine https://en.wikiquote.org/wiki/Alphonse_de_Lamartine
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