Most cells undergo the process of mitosis for growth and repair. However, some cells, such as neurons and muscle cells, no longer divide upon reaching full development.
Cells are the fundamental units that carry out vital functions necessary for the survival of an organism. To sustain life, most cells need to constantly divide. Cell division is classified into two types: mitosis and meiosis. While mitosis involves physical development and maintenance, meiosis ensures that an organism is able to reproduce.
An organism starts from a single cell, which continuously divides and multiplies through mitosis to eventually reach its adult form. Eukaryotic cells, such as the cells comprising plants and animals, undergo nuclear division and produce two identical daughter cells during mitosis. This process is broken down into five major phases: prophase, prometaphase, metaphase, anaphase and telophase. Interphase, which is the stage when the cell's genetic material is replicated, precedes the first phase of mitosis. After telophase, which is the last mitotic stage, cytokinesis occurs where the parent cell is separated into two duplicate daughter cells.
Mitosis is cyclical and repeats all throughout an organism's lifetime. In humans, the inevitable wear and tear that is normally associated with the aging process, causes damage to living cells. Injuries and accidents may also result in cell impairment. Mitosis plays an important role in replenishing the body with lost cells or in repairing damaged body parts.