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A point mutation is a change in a single nucleotide base pair in the DNA sequence. These mutations can occur during DNA replication, when DNA polymerase makes an error while copying the DNA. If this error is not corrected by proofreading mechanisms, it will become a permanent mutation in the daughter cells after mitosis.

Point mutations can result in various effects, including silent mutations (where there’s no effect on the protein), missense mutations (which lead to a different amino acid being incorporated), or nonsense mutations (which create a premature stop codon). Since replication is a critical phase in the cell cycle, any mistakes that occur during this process can ultimately lead to point mutations in the resulting cells.

While translocations and inversions can result from chromosomal rearrangements or errors during cell division, they are not typically categorized as mutations caused directly by replication errors. Translocation involves the transfer of a segment of DNA to a different chromosome, and inversion involves the reversal of a segment within the same chromosome; both are more complex rearrangements compared to the basic change of a single nucleotide in a point mutation.