Deoxyribonucleic acid (DNA) is the blueprint for building living organisms. DNA is comprised of a sugar-phosphate back bone and base pairs. The helical structure of DNA is due to the hydrophilic nature of the sugar-phosphate back bone and the hydrophobic nature of the base pairs. DNA is passed from parents to their offspring in segments known as genes. These genes are organized into units called chromosomes which tell your body which proteins to make and in what quantities. Each human has the same genes but due to mutations and variations in those genes, each person is unique.