The division of the cytoplasm, usually follows the nuclear division stage of mitosis and produces two daughter cells, each containing one of the daughter nuclei.
PATHWAYS TO CYTOKINESIS
- Furrowing
- Cell plate
The layer of microtubules that remains at the former spindle midpoint expands laterally until it stretches entirely across the dividing cell. As the layer develops, a band of microfilaments forms just inside the plasma membrane, forming a belt that follows the inside boundary of the cell in the plane of microtubule layer. Powered by motor proteins, the microfilaments slide together, tightening the band and constricting the cell. The constriction forms a groove or furrow in the plasma membrane. The furrow deepens until the daughter cell is completely separated.
CELL PLATE FORMATION
The layer of microtubules that persists at the former spindle midpoint serves as an organizing site for vesicles produced by ER and Golgi complex. As vesicles collect, the layer expands until it spreads entirely across the dividing cell. During this expansion, the vesicles fuse together and their contents assemble into a new cell wall, the cell plate, stretching completely across the former spindle midpoint. The junction separates the cytoplasm and its organelles into two parts and isolates the daughter nuclei in separate cells.
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