Which of the following correctly identifies the roles of the labeled components in the DNA replication process?

• A. Helicase unwinds the DNA double helix, DNA polymerase synthesizes new DNA strands, and primase adds RNA primers.
• B. Ligase unwinds the DNA double helix, primase synthesizes new DNA strands, and helicase adds RNA primers.
• C. DNA polymerase unwinds the DNA double helix, helicase synthesizes new DNA strands, and ligase adds RNA primers.
• D. Primase unwinds the DNA double helix, ligase synthesizes new DNA strands, and DNA polymerase adds RNA primers.

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the DNA replication process. DNA replication is the process by which a cell duplicates its DNA before cell division. It involves several enzymes, each with a specific role.
2. Step 2: Identify the role of helicase. Helicase is responsible for unwinding the DNA double helix by breaking the hydrogen bonds between the complementary base pairs, creating two single strands that serve as templates.
3. Step 3: Determine the role of primase. Primase synthesizes short RNA primers on the single-stranded DNA templates. These primers provide a starting point for DNA polymerase to begin DNA synthesis.
4. Step 4: Examine the role of DNA polymerase. DNA polymerase is the enzyme that synthesizes new DNA strands by adding nucleotides complementary to the template strand, starting from the RNA primer.
5. Step 5: Clarify the role of ligase. Ligase is responsible for joining Okazaki fragments on the lagging strand by forming phosphodiester bonds, ensuring the DNA strand is continuous.