During DNA replication, which protein stabilizes the unwound DNA strands by binding to single-stranded DNA and preventing reannealing?

• A. DNA polymerase III
• B. Single-strand binding proteins (SSBs)
• C. DNA ligase
• D. Helicase

Answer: (B)

Verified step by step guidance

1. Understand the process of DNA replication, which involves unwinding the double helix and synthesizing new strands.
2. Identify the role of helicase, which is to unwind the DNA double helix by breaking hydrogen bonds between base pairs.
3. Recognize that once the DNA strands are separated, they tend to reanneal or form secondary structures, which can interfere with replication.
4. Learn that single-strand binding proteins (SSBs) bind to the separated single-stranded DNA to stabilize it and prevent the strands from reannealing or forming hairpins.
5. Differentiate the roles of other proteins: DNA polymerase III synthesizes new DNA strands, and DNA ligase joins Okazaki fragments on the lagging strand.