Why must dna repication have to occur before a cell can divide by mitosis

I believe your question is about DNA replication, in which case the answer would be;

DNA replication must occur because existing cells will divide to produce new cells.

Explanation:

DNA replication is important because the DNA basically needs to be copied before cell division so that each new cell receives a full set of "instructions" or parameters.

adam ripon he cute then jared goff

answer; i do believe that the correct answer is; ///mendelian genes are at specific loci on the chromosome and, in turn, segregate during meiosis;