EVERYDAY SCIENCE

Detailed explanation-1: -One hundred fifty years ago, Friedrich Miescher discovered DNA when he isolated “Nuclein"-as he named it-from nuclei of human pus cells. Miescher recognized his isolate as a new type of molecule equal in importance to proteins. He realised that it is an acid of large molecular weight and high phosphorus content.

Detailed explanation-2: -Johannes Friedrich Miescher (13 August 1844 – 26 August 1895) was a Swiss physician and biologist. He was the first scientist to isolate nucleic acid in 1869. He also identified protamine and made a number of other discoveries.

Detailed explanation-3: -As early as 1869, Friedrich Miescher came across a completely new substance after extensive examinations and named it “nucleic”. He proved, amongst others, that nucleic is found in many different cells.

Detailed explanation-4: -Miescher recognised that he had discovered a novel molecule. Since he had isolated it from the cells’ nuclei he named it nuclein, a name preserved in today’s designation deoxyribonucleic acid.

Detailed explanation-5: -Miescher collected bandages from a nearby clinic and washed off the pus. He experimented and isolated a new molecule-nuclein-from the cell nucleus. He determined that nuclein was made up of hydrogen, oxygen, nitrogen and phosphorus and there was an unique ratio of phosphorus to nitrogen.