The nucleus is an organelle found in the center of a cell that serves to control the cell's function. It contains the DNA and other components necessary to regulate gene expression.Continue Reading
The hereditary information stored in the nucleus controls the cell's growth, reproduction, intermediary metabolism and protein synthesis. Less complex organisms, such as one-celled microbes, do not have a nucleus. All their genetic information is stored in their cytoplasm. The nucleus is only found in complex cells known as eukaryotes. It is located in a membrane called the nuclear envelope, separating the nucleus from the surrounding cytoplasm in the cell. Holes in the nuclear envelope allow for the transfer of specific molecules from the cytoplasm to the nucleus. This transfer of molecules is essential to regulating the functions of the cell.
The nucleus contains a semifluid substance called nucleoplasm, which stores chromatin. Chromatin is a string of packed-together DNA located in every nucleus. This DNA is essential to creating the genetic makeup and activity of the cell. The nucleus has an organelle in its center called the nucleolus, which is responsible for the creation of ribosomes. Some species have multiple nucleoli that are responsible for the organization of the nucleolus in new cells. The nucleolus disappears during cell division.Learn more about Cells