Animal cells undergo cytokinesis through a mechanism known as cleavage, wherein the cell membrane constricts inward to facilitate cell division.

Cytokinesis is a critical phase of the cell cycle that occurs after mitosis, the process whereby the cell’s nucleus divides. This division is driven by a structure called the contractile ring, which consists of two types of protein filaments: actin and myosin. The contractile ring forms just beneath the cell membrane at the metaphase plate, which is the region where the cell is set to divide.

The contractile ring operates similarly to a drawstring. As it contracts, it pulls the cell membrane inward in a process referred to as cleavage. This action creates a furrow or indentation around the center of the cell. As the contraction continues, the furrow deepens until the cell is effectively pinched into two distinct cells, each containing its own nucleus and an equal portion of the cytoplasm. This process can be visually compared to pinching a balloon in the middle until it splits into two smaller balloons.

It is noteworthy that cytokinesis in animal cells differs from that in plant cells. Given that plant cells possess a rigid cell wall, they cannot undergo inward pinching. Instead, plant cells form a structure known as the cell plate at the center of the cell, which eventually develops into a new cell wall that separates the two daughter cells.

Cytokinesis plays an essential role in cell biology, facilitating growth, repair, and reproduction in multicellular organisms. This process is tightly regulated, with numerous checks and balances in place to ensure that each daughter cell receives an equitable share of cytoplasm and organelles. Errors during cytokinesis can lead to cells with abnormal chromosome numbers, which may result in serious consequences, including the potential development of cancer. Therefore, understanding the mechanisms underlying cytokinesis is crucial not only for comprehending fundamental cell biology but also for gaining insights into various diseases.