Structure of nucleus: Nucleus

Nucleus, in biology, a specialized structure occurring in most cells (except bacteria and blue-green algae) and separated from the rest of the cell by a double layer, the nuclear membrane. The structure of a nucleus encompasses the nuclear membrane, nucleoplasm, chromosomes, and nucleolus. The nuclear membrane is a double-layered structure that encloses the contents of the nucleus. The outer layer of the membrane is connected to the endoplasmic reticulum. The cell nucleus is the most noticeable organelle within the eukaryotic cell, and perhaps the most important and defining feature of the eukaryotic cells. Most of the genetic material (DNA) is contained in the nucleus, while a small amount of it is found in mitochondria. The majority of human cells have a single nucleus, although there are several cell types that have multiple nuclei (e.g. osteoclasts) or don't have a nucleus at all (erythrocytes). Since the structure of the nucleus is an ... What is a Nucleus The nucleus is a double membrane-bound organelle located centrally only in a eukaryotic cell, enclosing the DNA, the genetic material. It is the most important and defining feature of all higher organisms, including plant and animal cells, whose main function is to control and coordinate the functioning of the entire cell.