The four nitrogenous bases that make up the DNA structure are divided into two groups, called purines and pyrimidines. Adenine and guanine are purines, and chemically are double-ringed structures - a five cornered ring and a six cornered ring. They are much larger than pyrimidines.
James Mason (I) (1909â1984) James Mason was a great English actor of British and American films. He was born in Yorkshire, and attended Marlborough and Cambridge, where he discovered acting on a lark, and abandoned a planned career as an architect. Following work in stock companies, he joined the Old Vic under the guidance of Sir Tyrone Guthrie and of Alexander Korda, who ...
George Mason IV (December 11, 1725 â October 7, 1792) was an American Patriot, statesman and a delegate from Virginia to the U.S. Constitutional Convention.is efforts eventually succeeded in convincing the Federalists to add the first 10 amendments of the Constitution. These amendments, collectively known as the Bill of Rights, were based on the earlier Virginia Declaration of Rights, which Mason had drafted in 1776. On the issue of slavery, Mason walked a fine line.