What happens to one strabd of DNA when there a base on the other strand?

When there is a base on one strand of DNA, it pairs with a complementary base on the opposite strand through hydrogen bonding. For example, adenine (A) pairs with thymine (T), and guanine (G) pairs with cytosine (C). This specific base pairing is essential for maintaining the DNA double helix structure and ensures accurate replication and transcription of genetic information. If a base is mismatched, it can lead to mutations or errors during DNA replication.