Cell Division

The only way to make a new cell is to duplicate a cell that already exists. Three main functions of cell division are:

• Reproduction
• Growth and development
• Tissue renewal

The fundamental function of the cell cycle is to accurately copy the enormous length of DNA in the chromosome, and to segregate the copies precisely into two genetically identical daughter cells. In order to divide, a cell must first go through a series of events:

• Signal. The cell receives a signal for cell division related to the needs of the entire organism.

• Replication. The genetic material that makes up an organism is called the genome. Eukaryotic genomes consist of a number of DNA molecules that are enormous in length (almost 2 m in human cell). All of this DNA must be copied so that each daughter cell has a complete genome.

• Segregation. The newly replicated chromosomes come in pairs that are called sister chromatid. A mechanism, mitosis, will segregate the sister chromatid into two new nuclei.

• Cytokinesis. The division of cytoplasm, cytokinesis, is preceded by the division of the genetic material in the nucleus, like mitosis.