Principle purpose of this lecture is to present on Structure of DNA. Here briefly describe on Genetic control of protein structure and function of DNA. DNA is made up of six smaller molecules — a five carbon sugar called deoxyribose, a phosphate molecule and four different nitrogenous bases (adenine, thymine, cytosine and guanine). The backbone of DNA is based on a repeated pattern of a sugar group and a phosphate group. The full name of DNA, deoxyribonucleic acid, gives you the name of the sugar present – deoxyribose.