The Nucleus
The Nucleus is a highly specialized Organelle that serves as the information and administrative center of Eukaryotic Cells. It has two primary functions: it stores the cell's Hereditary-Material, or DNA, and it coordinates the cell's activities, which include growth, intermediary metabolism, Protein-Synthesis, and Cell-Division.
Structure and Composition
The Nucleus is spherical or oval in shape and is enclosed by a double membrane called the Nuclear-Envelope. This membrane is perforated by Nuclear-Pores, which are complex structures that regulate the exchange of materials, such as RNA and Proteins, between the Nucleoplasm and the Cytoplasm. Within the Nucleus, the DNA is organized into Chromosomes, which are composed of Chromatin—a complex of DNA and Histones. The Nucleolus is a prominent sub-nuclear structure where Ribosomes are synthesized and assembled.
Function and Regulation
The Nucleus protects the Genome and regulates Gene-Expression. It is the site of Transcription, where Messenger-RNA is created to carry instructions to the rest of the cell. According to the National Human Genome Research Institute, the nucleus is critical for maintaining the integrity of Genes. Additional research on nuclear dynamics is available via Nature Education.