The Role of the Nucleus

The nucleus is the organising centre of the cell because it houses the chromosomes, the structures that carry the cell's hereditary information. Three roles make the nucleus indispensable to cell division. First, the chromosomes control the day-to-day activities of the cell by determining which proteins are made and when. Second, whenever a cell divides, the genetic information in the chromosomes must be copied accurately and distributed so that each daughter cell receives a complete set - this copying and equal distribution is the central job of mitosis. Third, in sexual reproduction, the hereditary information carried in the nucleus of a sperm and an egg is combined when the two gametes fuse, so that characters are passed from parents to offspring. Without an intact, correctly dividing nucleus, a daughter cell would either lack essential genetic instructio …