DNA or deoxyribonucleic Acid can be chemically categorized as a nucleic acid. It is composed of three basic units; Nitrogenous bases (Adenine, Guanine, Thymine, and Cytosine), sugar molecule (Deoxyribose) and back bone made up of phosphate molecules. Biologically, the role played by this molecule is related to storage and transmission of information within the cell. Almost universally compared to a blueprint, the information contained within this molecule is vital to the functioning of the cell and the organism as a whole. The structure of this molecule is unique in more ways than one. The four nitrogenous bases form pairs with one another in the following manner, Adenine (A) always pairs with Thymine (T) whereas Cytosine (C) always pairs with Guanine (G). This unique specificity allows the molecule to assume a double stranded shape zip-like configuration. The unit composed of a Nitrogenous base, the sugar moiety and the phosphate molecule is known as the Nucleotide. The first carbon atom of the sugar is connected to the base and the fifth Carbon is connected to the Phosphate moiety. The continuously connected bases on one strand are paired as per the above pattern thus resulting into two anti-parallel strands of DNA are formed that coil around one another giving the molecule its characteristic double helical shape. This anti-parallel nature allows each strand to act as a template for the synthesis of the complementary strand. This unique structure was elucidated by Dr. James Watson and Dr. Francis Crick.

DNA Simplified Structure

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