Difficulty: Easy
Correct Answer: DNA polymerase
Explanation:
Introduction:
Replication requires a template, primers, and enzymes that catalyze phosphodiester bond formation. This question focuses on the enzyme that actually polymerizes deoxyribonucleotides into DNA by base pairing with the template strand.
Given Data / Assumptions:
Concept / Approach:
Identify the role of each enzyme: helicase unwinds, primase lays RNA primers, DNA polymerase extends DNA, ligase seals nicks, and RNA polymerase transcribes RNA, not DNA. Therefore, DNA polymerase is responsible for adding complementary bases to DNA during replication.
Step-by-Step Solution:
Verification / Alternative check:
Biochemical assays show polymerase activity as template- and primer-dependent incorporation of labeled nucleotides into acid-insoluble DNA.
Why Other Options Are Wrong:
Common Pitfalls:
Using “replicase” generically; in eukaryotes, multiple DNA polymerases (e.g., δ, ε) share roles.
Final Answer:
DNA polymerase.
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