What is the last phase of the Cell Cycle? (This is when the genetic material has already been duplicated and what is left to do is to physically split up the rest of the cell - organelles, cytoplasm, etc. - into two separate, identical cells.)

mitotic phase

Explanation:

The cell cycle has two phases the Interphase and mitosis. Interphase is the growth phase where the cell prepares itself for the cell division. It is divided into three phase G1 phase( Cell growth),S phase ( DNA synthesis) and G2 phase(cell growth).

Mitotic phase has a multiple steps this is where the duplicated chromosomes are aligned or arranged, separated, and move into two new, identical daughter cells(cytokinesis)

The first step in the mitotic phase is called karyokinesis or nuclear division where the chromosomes are separated and move in opposite direction and the second portion of the mitotic phase, called cytokinesis which is the physical separation of the chromatids into the two daughter cells.