Mitotic phase

Prophase

• Chromosomes condense and become visible.

• Spindle fibers begin to form from the centrosomes.

• The nuclear envelope breaks down.

• Centrosomes start moving toward opposite poles.

Prometaphase

• Chromosomes continue to condense.

• Kinetochores appear at the centromeres of each chromatid.

• Mitotic spindle microtubules attach to the kinetochores.

Metaphase

• Chromosomes align at the metaphase plate (center of the cell).

• Each sister chromatid is attached to spindle fibers originating from opposite poles.

Anaphase

• Centromeres split in two, separating sister chromatids (now called chromosomes).

• Chromosomes are pulled toward opposite poles of the cell.

• Spindle fibers begin to elongate the cell.

Telophase

• Chromosomes arrive at opposite poles and begin to decondense.

• Nuclear envelopes reform around each set of chromosomes.

• Mitotic spindle breaks down, and spindle fibers continue to push poles apart.

Cytokinesis

• Animal Cells: A cleavage furrow forms to separate the two daughter cells.

• Plant Cells: A cell plate forms, which will develop into a new cell wall separating the daughter cells.