Mitosis

The M phase of the cell cycle is the process known as mitosis. Some scientists classify cytokinesis as separate from mitosis, but still in the M phase. Mitosis is split into 4 distinct phases plus cytokinesis.

Prophase is the longest phase of mitosis. Chromatin condenses to form chromosomes, centrioles move to the poles, spindles form, the chromosomes attach to the spindle fibers at the centromere and the nuclear envelope breaks down.

Metaphase is usually brief. Chromosomes line up across the center of the cell and microtubules connect the centromere of each chromosome to the two spindles at the poles.

Anaphase is the next phase. The spindles split the sister chromatids and when they reach the poles and stop moving, anaphase is over.

Telophase if the final phase. The distinct, condensed chromosomes disperse, the nuclear envelope reforms around the chromosomes, and the spindles break apart.

Cytokinesis is the last step of cell division. This involves the division of cytoplasm and the cell membrane pinches shut, separating the two daughter cells.

This Krispy Kreme illustration is actually a great example of what this looks like:

Click through to see it full size.

One Response

  1. W00t! Krispy Kreme making science all worth it!

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