Cytokinesis involves the division of the cytoplasm following mitosis to form two daughter cells. It begins before nuclear division is complete. In animal cells, actin filaments contract to form a cleavage furrow that deepens and separates the cell into two daughters. In plant cells, membrane vesicles gather at the equator and fuse to form a cell plate, which grows outward and fuses with the parent cell's membrane to produce new cell walls.