During which phase of mitosis do chromosomes align at the cell's equatorial plane?

During mitosis, chromosomes align at the cell's equatorial plane during the metaphase. This phase follows prophase, where the chromatin condenses into visible chromosomes and the mitotic spindle begins to form. By the time the cell reaches metaphase, the chromosomes are fully condensed, and the spindle fibers attach to the centromeres of the chromosomes.

The alignment at the equatorial plane, also referred to as the metaphase plate, is crucial for ensuring that when the cell progresses to anaphase, each sister chromatid will be pulled apart evenly to opposite poles of the cell. This alignment allows for accurate and equal distribution of genetic material to the daughter cells. The mitotic spindle plays an essential role here, as it helps to maintain the structure of the chromosomal arrangement during this critical phase of cell division.