1. Formation of a cleavage furrow: This is a shallow groove in the cell surface, formed by a ring of microfilaments made of the protein actin.
2. Contraction of the cleavage furrow: The microfilaments contract, pulling the plasma membrane inward, eventually pinching off the cell into two daughter cells.
3. Formation of the contractile ring: This is a ring of actin filaments that forms just beneath the plasma membrane, and is responsible for the actual pinching off of the cell.
The following is not involved in cytoplasmic division in animal cells:
* Formation of a cell plate: This is a structure that forms in plant cells during cytokinesis, and is involved in the formation of the new cell wall between the two daughter cells.
Therefore, the answer to your question is: Formation of a cell plate**.
