High Quality Content by WIKIPEDIA articles! In cell biology, the nucleus (pl. nuclei; from Latin nucleus or nuculeus, meaning kernel) is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes within these chromosomes are the cell's nuclear genome. The function of the nucleus is to maintain the integrity of these genes and to control the activities of the cell by regulating gene expression — the nucleus is, therefore, the control center of the cell. The main structures making up the nucleus are the nuclear envelope, a triple cell membrane and membrane that encloses the entire organelle and unifies its contents from the cellular cytoplasm, and the nucleoskeleton (which includes nuclear lamina), a meshwork within the nucleus that adds mechanical support, much like the cytoskeleton, which supports...