Mitosis, which occurs in both animal and plant cells, is a four phase process during which the nucleus of the cell divides, before the cell itself divides. This video shows mitosis occurring first in an animal cell and then in a plant cell, using both computer animation and remarkable microscopy of the nucleus within live cells. Before mitosis begins, the DNA replicates. During the four phases of mitosis, which are prophase, metaphase, anaphase, and telophase; the replicated DNA becomes densely coiled into its chromosome form, is aligned across the middle of the nucleus, then separated into single chromosomes which are drawn to opposite ends of the cell. As two nuclei form, the cytoplasm of the cell divides in a process called cytokinesis, and so forms two identical offspring cells enclosed within cell membranes. However, cytokinesis in a plant cell additionally forms a cell wall, which surrounds the cell membrane. The result of mitosis is two cells, be they animal or plant, with DNA identical to the parent cell.

Originally released by Benchmark Media, 2006. Streaming video file encoded with permission for digital streaming by Infobase on April 30, 2015.

Interphase: DNA Replication (2:36); --Mitosis: Animal Cell Nucleus Division (3:50); -- Mitosis: Plant Cell Nucleus Division (2:58); -- Mitosis (0:11); .