Almost every cell in the human body is replaced every few years through the process of

Mitosis and meiosis are simply cell division processes that occurs differently, they're characteristically divergent from each other according to their function and structure. Mitosis is the cell division that happens in all cells in the human body except sperm and egg cells. They produce diploid cells. Meiosis on the other hand is responsible for the cell division of the gametes, spermatogenesis (sperm cells) and oogenesis (egg cells), such haploid cells. Take for instance your integumentary system, layer of the skin in which your stratum basale always produces new epithelial cells (via mitosis) to take over until the outer layer, called stratum corneum (a continous replaced dead cells in this layer).