How does cytokinesis occur in animal cells?

Cytokinesis in animal cells occurs through a process known as cleavage furrow formation. During this process, the cell membrane is pinched inward at the equator of the cell, which effectively divides the cytoplasm and creates two separate daughter cells. This inward pinching creates a furrow that deepens until the cell is completely separated into two cells.

The reason this process is described as occurring from the outside in is due to the mechanism by which the cleavage furrow forms; the actin filaments and myosin motor proteins contract just under the cell membrane, pulling the membrane tighter together from the outer edges. As the furrow deepens, it eventually meets at the center, completing the division of the cytoplasm. This method is characteristic of animal cells, which differs from plant cells, where a cell plate forms from the inside out to separate the daughter cells.