ABSTRACT
The birth of Deoxyribonucleic acid (DNA) research began over a hundred years ago with the study of heredity in flowers. Miescher discovered a new chemical inside the nuclei of the white blood cells. Miescher called it nuclein, but he had no idea that he had just discovered DNA. Early samples of nuclein were a mixture of both Ribonucleic acid (RNA) and DNA. In the early 1900s, Danish botanist Wilhelm Johannsen reconfirmed Mendel's earlier work, using beans. He also concluded that units inside the beans were responsible for passing on traits. Instead of making a copy of the entire DNA, part of the double helix could unzip and makes a copy of just one gene Johannsen also coined the words genotype and phenotype. Recombinant DNA contains genes that would not be found naturally in a species. The thymus is a gland just below the base of the neck behind the breastbone that is part of the immune system.
