Question

which replication enzyme is responsible for checking new dna and correcting errors in the base sequence of the growing strand?

a. primase
b. dna polymerase
c. exonuclease
d. dna ligase

Explanation:

Identify the function of DNA polymerase proofreading

DNA polymerase synthesizes the new DNA strand by adding nucleotides complementary to the template strand. During this process, it performs a proofreading function to check for mismatched bases and correct errors immediately.

Evaluate the given options

• Primase: Synthesizes RNA primers to start DNA replication.
• DNA polymerase: Synthesizes the growing strand and proofreads/corrects errors.
• Exonuclease: Refers to an enzymatic activity (which DNA polymerase possesses) rather than the primary replication enzyme itself.
• DNA ligase: Joins Okazaki fragments on the lagging strand.

Answer:

• (A) Primase
• (B) DNA polymerase (Correct answer)
• (C) Exonuclease
• (D) DNA ligase