One strand of a fragment of duplex DNA has the sequence 5'-ATCGACCTGATC-3'.

Identify the bond that joins one strand of a DNA duplex to the other strand.

Key Concepts

Hydrogen Bonds

Hydrogen bonds are weak interactions that occur between the nitrogenous bases of the two DNA strands. In a DNA duplex, adenine pairs with thymine through two hydrogen bonds, while cytosine pairs with guanine through three hydrogen bonds. These bonds are crucial for the stability of the DNA double helix, allowing the strands to separate during processes like replication and transcription.

Base Pairing Rules

Base pairing rules dictate how nitrogenous bases in DNA pair with each other. Specifically, adenine (A) pairs with thymine (T), and cytosine (C) pairs with guanine (G). This complementary pairing is essential for the accurate replication of DNA and the transmission of genetic information, ensuring that the genetic code is preserved across generations.

DNA Structure

DNA is structured as a double helix, consisting of two antiparallel strands that are held together by base pairs. Each strand is composed of a sugar-phosphate backbone and nitrogenous bases that extend inward. The antiparallel nature of the strands (one running 5' to 3' and the other 3' to 5') is critical for the mechanisms of DNA replication and transcription, influencing how enzymes interact with the DNA.