For this to happen the DNA must replicate itself exactly. When DNA replicates itself and the cell divides both of the new cells that are produced contain the exact same DNA (barring mutations) which means both new cells can code to make the same proteins.
Americium was first produced in 1944 by the group of Glenn T. Seaborg at the University of California, Berkeley. Although it is the third element in the transuranic series, it was discovered fourth, after the heavier curium.
Beryllium metal was isolated in 1828 from beryllium chloride (BeCl 2) by reacting this with potassium. Beryllium was to play a historic role in advancing our knowledge of atomic theory since it helped uncover the fundamental particle, the neutron. This was discovered in 1932 by James Chadwick who bombarded a sample of beryllium with the alpha-rays (which are helium nuclei) emanating from radium.