Cytokinesis is the final step in cell division, following either mitosis or meiosis, and it involves the physical separation of the two daughter cells that have been created during the earlier stages of cell division. Its primary purpose is to ensure that each daughter cell receives the appropriate complement of organelles, cytoplasmic components, and genetic material. Cytokinesis is different in animal cells and plant cells.
In **Animal Cells:**
During cytokinesis in animal cells, a contractile ring composed of actin filaments forms just beneath the cell membrane at the center of the cell, constricting like a drawstring. This contraction process continues until the cell is pinched into two separate daughter cells. Each daughter cell then inherits roughly equal portions of the cytoplasm, organelles, and other cellular components.
In **Plant Cells:**
Cytokinesis in plant cells is slightly different due to the presence of a rigid cell wall. Instead of a contractile ring, plant cells build a new structure called the **cell plate** in the middle of the cell. The cell plate consists of vesicles containing cell wall materials and other components. These vesicles fuse together, gradually forming a new cell wall that divides the parent cell into two daughter cells. Eventually, the new cell wall fully develops, and the two daughter cells become separate entities.
At the end of cytokinesis, one parent cell has successfully divided into two daughter cells, and each daughter cell has its own set of cellular components, organelles, and genetic material. These daughter cells are genetically identical to the parent cell (in mitosis) or have half the genetic material (in meiosis) and are ready to carry out their respective functions and continue the life cycle of the organism.