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 ...
Who is James Comey? James Comey is an American lawyer and the current Director of the Federal Bureau of Investigation (FBI). He previously served as the United States Deputy Attorney General in the George W. Bush administration from 2003 to 2005. He is also a former member of Republican Party. James Comey: Birth Facts, Family, and Childhood