preexisting cells
No matter what the cell, all cells come from preexisting cells through the process of cell division. This is one of the core concepts of the Cell Theory. The cell may be the simplest bacterium or a complex muscle, bone, or blood cell. The cell may comprise the whole organism, or be just one cell of trillions. But whatever type of cell it is, it comes from a preexisting cell. And the new cell is genetically identical to its parent cell - that is, it has exactly the same DNA.