NEET BIOLOGY

Detailed explanation-1: -Most of the mistakes during DNA replication are promptly corrected by DNA polymerase by proofreading the base that has been just added ([link]). In proofreading, the DNA pol reads the newly added base before adding the next one, so a correction can be made.

Detailed explanation-2: -DNA polymerase proofreading is the first process for fixing nucleotide mistakes in DNA.

Detailed explanation-3: -During DNA synthesis, most DNA polymerases “check their work, ” fixing the majority of mispaired bases in a process called proofreading. Immediately after DNA synthesis, any remaining mispaired bases can be detected and replaced in a process called mismatch repair.

Detailed explanation-4: -DNA polymerase proofreading is a spell-checking activity that enables DNA polymerases to remove newly made nucleotide incorporation errors from the primer terminus before further primer extension and also prevents translesion synthesis.

Detailed explanation-5: -At least five major DNA repair pathways-base excision repair (BER), nucleotide excision repair (NER), mismatch repair (MMR), homologous recombination (HR) and non-homologous end joining (NHEJ)-are active throughout different stages of the cell cycle, allowing the cells to repair the DNA damage.