The complementary base of adenine in DNA is thymine. In DNA, adenine always pairs with thymine, forming two hydrogen bonds between them. This pairing is essential for the structure and function of DNA because it ensures the accurate replication of genetic information during cell division.
The base pairing rules in DNA are as follows:
1. Adenine (A) pairs with thymine (T) through two hydrogen bonds.
2. Guanine (G) pairs with cytosine (C) through three hydrogen bonds.
Therefore, in a DNA strand, if you have adenine (A) on one side, the complementary base on the other side will be thymine (T), and vice versa. This complementary base pairing is crucial for maintaining the genetic code and stability of the DNA molecule.
