Telophase

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A cell during telophase that has almost completed cytokinesis. The nuclei in both cells have already formed. An arrow points to a centrosome that can still be seen.

Telophase: The pinching is known as cleavage furrow. Note the decondensing chromosomes.

Telophase (sometimes spelled telephase), from the ancient Greek "τελος" (end) and "φασις" (stage), is a stage in either meiosis or mitosis in a eukaryotic cell reversing the effects of prophase and prometaphase events. During those events, the nucleus was dissolved and the chromatin in the cell was condensed into chromosomes. Telophase thus "cleans up" the secondary after-effects of mitosis.

At this stage, the non-kinetochore microtubules continue to lengthen, further elongating the cell. Corresponding sister chromosomes, which are the results of anaphase, attach at opposite ends of the cell. A new nuclear envelope, using fragments of the parent cell's nuclear membrane, forms around each set of separated sister chromosomes. Both sets of chromosomes, now surrounded by new nuclei, unfold back into chromatin.

Cytokinesis, if slated to occur, usually occurs at the same time the nuclear envelope is reforming, although they are distinct processes. In animal cells, a cleavage furrow develops where the metaphase plate used to be, pinching off the separated nuclei.

In plant cells, vesicles derived from the Golgi apparatus move to the middle of the cell along a microtubule scaffold called the phragmoplast. This structure directs packets of cell wall materials which coalesce into a disk-shaped structure called a cell plate. The cell plate grows out centrifugally and eventually develops into a proper cell wall, separating the two nuclei.

Each daughter cell has a complete copy of the genome of its parent cell, and mitosis is complete.