Why are complementary bases important? ... In DNA, the nitrogen bases are named guanine, cytosine, adenine, and thymine, and they will connect with each other by forming bonds (specifically, hydrogen bonds) with their hydrogen atoms. Guanine always bonds with cytosine, which makes them a pair of complementary bases.

Why do bases have to be complementary?

Complementary base pairing is important in DNA as it allows the base pairs to be arranged in the most energetically favourable way; it is essential in forming the helical structure of DNA. It is also important in replication as it allows semiconservative replication.

Why is DNA described as having complementary bases?

Base Pairs

Only certain types of base pairing are allowed. For example, a certain purine can only pair with a certain pyrimidine. This means Adenine pair with Thymine, and Guanine pairs with Cytosine. This is known as the base complementary rule because the DNA strands are complementary to each other.