What type of bond is formed between cytosine bases on opposite strands of DNA?

Cytosine bases on opposite strands of DNA are held together by hydrogen bonds. In the double helix structure of DNA, bases form complementary pairs—adenine pairs with thymine, and cytosine pairs with guanine. The specific interaction between cytosine and guanine involves three hydrogen bonds, which provides stability to the DNA structure while still allowing the strands to separate during processes such as DNA replication and transcription.

The weak nature of hydrogen bonds is crucial because it allows the strands of DNA to be easily unwound without breaking the backbone of the molecule, thereby facilitating vital biological processes. Understanding the role of hydrogen bonds in base pairing helps to clarify how genetic information is accurately replicated and transmitted.