What is cytokinesis primarily responsible for?

Cytokinesis is primarily responsible for the splitting of the cytoplasm during cell division. After mitosis, which is the process of nuclear division, cytokinesis ensures that the cytoplasm is divided into two separate daughter cells, each containing its own set of organelles and sufficient cytoplasmic material to function independently. This process typically follows mitosis and is crucial for the successful completion of the cell cycle, allowing for the formation of two individual cells rather than one large cell with two nuclei.

While the formation of a new cell membrane is an integral part of cytokinesis, it is the actual division of the cytoplasm that characterizes this phase. This process is tightly regulated and involves various components of the cell's cytoskeleton to ensure that the cell divides evenly. Other choices such as DNA replication and the formation of the spindle apparatus pertain to different stages of the cell cycle; DNA replication occurs during S phase, and the spindle apparatus is formed during prophase of mitosis. Thus, the role of cytokinesis is distinct and central to achieving independent daughter cells.