Write the names of four nitrogenous bases in the DNA.
DNA
1. DNA or deoxyribonucleic acid is composed of nucleotides.
2. Nucleotides are formed of (a) a nitrogenous bases, (b) 5-carbon deoxyribose sugar (C5H10O4) and (c) phosphate group (PO4-).
Nitrogenous bases
1. Purine and pyrimidine are derived from heterocyclic rings which are produced by nucleotide hydrolysis.
2. There are five different nucleotide bases present in the genetic material - three pyrimidine bases and two purine bases.
Pyrimidine bases
1.The pyrimidine bases are thymine, cytosine and uracil.
2. Thymine and cytosine are present in DNA whereas uracil is present in RNA instead of thymine.
Purine bases
The purine bases are adenine and guanine.
Thus, the four nitrogenous bases in the DNA are adenine, guanine, cytosine and thymine.