Question

Give one example of a nitrogen base in DNA.

Answer 1

1. A DNA molecule has four nitrogen bases - adenine, guanine, cytosine, and thymine.
2. These nitrogenous bases are categorized as purines and pyrimidines.
3. Purines contain two rings - one five-membered ring and one six-membered ring while pyrimidines contain a single six-membered ring.
4. Adenine and thymine are purines while guanine and cytosine are pyrimidines.
5. Adenine and thymine are complementary to each other and linked by two hydrogen bonds.
6. Cytosine and guanine are complementary to each other and linked by three hydrogen bonds.

Note: An example of a nitrogen base in DNA can be any of these - adenine, cytosine, thymine, and guanine.