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Historic facts this week

February 22, 2014

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Dolly — the sheep

February 22, 1997

A SHEEP named Dolly was cloned by scientists in Edinburgh and was hailed as one of the most significant breakthroughs of the decade. Dolly was the world’s first successfully cloned mammal, created at the Roslin Institute in Edinburgh; it was actually born on July 5, 1996, although her arrival was not revealed for some time. Dolly the sheep is an exact genetic duplicate of the animal from which the single cell was taken.


First toothbrush with nylon bristles

February 24, 1938

THE first toothbrush with nylon bristles was introduced and was called Doctor West’s Miracle Toothbrush. A scientist at DuPont de Nemours (American chemical company) invented nylon in the same year and the first application of nylon was done in toothbrush bristles. Similar to the type we use today, the toothbrush was first invented in China in 1498 with bristles made of coarse hairs taken from the back of a hog’s neck and attached to a bamboo stick or bone.


Chemical structure of DNA discovered

February 28, 1953

CAMBRIDGE University scientists James D. Watson and Frances H.C. Crick announced that they have determined the double-helix structure of DNA, the molecule containing human genes. The DNA — short for deoxyribonucleic acid — was discovered in 1869 but the structure was yet not known. Watson and Crick research determined that the structure of DNA was a double-helix polymer, or a spiral of two DNA strands. According to their findings, DNA replicated itself by separating into individual strands, each of which became the template for a new double helix.

Sources: bbc.co.uk; history.com; historyorb.com