AP BIOLOGY

Detailed explanation-1: -Although few people realize it, 1869 was a landmark year in genetic research, because it was the year in which Swiss physiological chemist Friedrich Miescher first identified what he called “nuclein” inside the nuclei of human white blood cells.

Detailed explanation-2: -Johann called this mysterious substance ‘nuclein’, because he believed it had come from the cell nucleus?. Unbeknown to him, Johann had discovered the molecular basis of all life – DNA. He then set about finding ways to extract it in its pure form. Swiss chemist, Friedrich Miescher.

Detailed explanation-3: -Concept 15 DNA and proteins are key molecules of the cell nucleus. In 1869, Friedrich Miescher isolated “nuclein, ” DNA with associated proteins, from cell nuclei. He was the first to identify DNA as a distinct molecule. Phoebus Levene was an organic chemist in the early 1900’s.

Detailed explanation-4: -How Was DNA Discovered? DNA was discovered in 1869 by Swiss researcher Friedrich Miescher, who was originally trying to study the composition of lymphoid cells (white blood cells). Instead, he isolated a new molecule he called nuclein (DNA with associated proteins) from a cell nucleus.

Detailed explanation-5: -In 1869, Johann Friedrich Miescher discovered a new substance in the nucleus of living cells. The substance, which he called nuclein, is now known as DNA, yet both Miescher’s name and his theoretical ideas about nuclein are all but forgotten.