Certain parts of the brain govern specific functions. For example, the cerebellum is involved with coordination; the hippocampus with memory. Nerve cells (neurons) are the basic unit of communication in the brain.
Eukaryotic organisms use mitosis to reproduce sexually. In mitosis, the parent cell is divided into two daughter cells which be identical to the parent cell. Edit
Asexual reproduction in single-celled organisms. 1  Single-celled organisms which use asexual reproduction can do so very rapidly simply by dividing into two equal halves. 2  In yeasts the cell does not divide equally in two halves; instead, there is a large mother cell and a smaller daughter cell.