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Nucleus Structure and Function | Video 4

Nucleus is the controlling centre of the cell. It contains most of the genes of the eukaryotic cell. (some genes are present on chloroplast and mitochondria). Nucleus was reported first time by Robert Brown in 1831. The nucleus is enclosed in nuclear envelop. The inside of nuclear membrane region is called nucleoplasm. The nuclear envelop is a double membrane structure made up of protein and lipids. The membrane is perforated by pores structures by which the transport of protein and mRNA etc Take place between the cytoplasm and nucleoplasm. Nucleoplasm consist of enzymes, nucleic acid, Protein, lipid, minerals etc. Within the nucleus protein and DNA form the tangled complex structure called chromatin, and when cell is dividing the chromatin condensed to form chromosomes. Each chromosome is made up of Arms called Chromatids and the central region to which the chromatids attached called centromere. Each Eukaryotic cell have a specific set of chromosomes. For Example Typical human cell contains 46 number of chromosomes with the exception of sex cells ( egg and sperm) which have 23 number of chromosomes. Another prominent structure inside the nucleus is nucleolus where the synthesis of ribosomal RNA occure and also the synthesis of ribosomes occurs. Functions of Nucleus Nucleus control all the activities of the cell Nuceus contain hereditary material which transfer characteristics to offspring Nucleus directs protein synthesis Inside the nucleus at the region of nucleolus synthesis of ribosomes occur.