Here's why:

* Cell division is the process by which a single cell divides into two or more daughter cells.

* DNA contains the genetic instructions for the cell.

* Each daughter cell needs a complete copy of the DNA to function properly.

* DNA replication ensures that each new cell receives a complete set of chromosomes (DNA molecules).

There are two main types of cell division:

* Mitosis: This produces two identical daughter cells, each with a full set of chromosomes. This is used for growth, repair, and asexual reproduction.

* Meiosis: This produces four daughter cells with half the number of chromosomes as the parent cell. This is used for sexual reproduction.

In both cases, DNA replication must occur before cell division can proceed.