The DNA molecule consists of three parts *nitrogenous base *deoxyribose sugar and *phosphate group.
The nitrogenous bases are nothing but cyclic carbon molecules that may or may not contain nitrogen groups attached to it. They are divided into two types :purines and pyrimidines.the purine consists of the adenine and guanine bases whereas the pyrimidines consists of the thymine and cytosine.the nitrogenous bases are attached to sugar molecule.the sugar molecule is pentose in structure.it is called the deoxyribose as it is nothing but the ribose sugar that lacks the oxygen molecule in its 2' position.the 5' carbon is attached to the phosphate group .the phosphate is a pentavalent compound with a double bonded oxygen and three single bond hydroxyl molecules
The nitrogenous bases are nothing but cyclic carbon molecules that may or may not contain nitrogen groups attached to it. They are divided into two types :purines and pyrimidines.the purine consists of the adenine and guanine bases whereas the pyrimidines consists of the thymine and cytosine.the nitrogenous bases are attached to sugar molecule.the sugar molecule is pentose in structure.it is called the deoxyribose as it is nothing but the ribose sugar that lacks the oxygen molecule in its 2' position.the 5' carbon is attached to the phosphate group .the phosphate is a pentavalent compound with a double bonded oxygen and three single bond hydroxyl molecules