Question

How many types of nucleotides are in dna, and how do they differ?

Answer 1

There are 4 nucleotides. Guanine (G), Cytosine (C), Thymine (G) and Adenine (A).
C and T are called pyrimidines, and are longer than G and A.
G and C connect using 3 hydrogen bonds, but A and T bond using only 2.