Cells have the ability to grow, have particular functions, and replicate during their life. Although cell enlargement is part of organismal growth, cell replication is also required and allows growth without each cell becoming too large. All of these activities are part of a repeating set of events known as the cell cycle. The major feature in the cell cycle is cellular replication and what enables for cellular replication is the process of mitosis. Mitosis is the only part of the cell cycle, and the remainder of the cycle consists of interphase, cytokinesis, gap 1, synthesis, and gap 2 phases. But cell division and reproduction can occur in two ways mitosis (which I just mentioned), and meiosis. Mitosis is used by single celled organisms to reproduce; it is also used for the organic growth of tissues, fibers, and membranes. While meiosis is useful for sexual reproduction of organisms; the male and female sex cells, the sperm and egg combined to create a new biological organism, in other words a baby.
Mitosis is the replication and division of the nucleus of a eukaryotic cell in preparation for cytokinesis. Cytokinesis is the division of the cell and follows immediately after mitosis. During mitosis, replicated chromosomes within the cell are separated into two identical sets. Each of the two new nuclei has a full set of chromosomes containing a copy of all the genetic material for the organism. Mind that only eukaryotic cells go through this process; prokaryotic cells lack a nucleus so they undergo binary fission in order to replicate their chromosome. Interphase basically starts off the cell cycle. Stages in interphase are G1, S, and G2. The G1 stage of the cell cycle occurs after mitosis and cytokinesis, and is when the majority of cellular activity for the functions of the cell occurs. Many cell-specific proteins and other molecules are produced for the metabolism of the cell during this stage.