Final answer:
Mismatch repair corrects errors in DNA replication, preventing mutations and maintaining the accuracy of the DNA sequence.
Step-by-step explanation:
Mismatch repair corrects the errors after the replication is completed by excising the incorrectly added nucleotide and adding the correct base. This process helps maintain the accuracy of DNA replication by fixing any mistakes. Without mismatch repair, the overall rate of mutation would be much higher because the errors would not be corrected, leading to permanent changes in the DNA sequence, which can have detrimental effects.
For example, if there is a mismatched base pair caused by an error in replication, the mismatch repair enzymes recognize the incorrect base and remove it from the DNA. Then, the correct base is added to replace the incorrect one. This step-by-step process ensures that mistakes are fixed, preventing mutations from occurring.
Therefore, mismatch repair plays a crucial role in maintaining the integrity of the DNA sequence and reducing the overall rate of mutation.