Nucleus Division

Function of Nucleus Contains genetic information Governs genetic expression, and thereby other vital cell functions Facilitate DNA replication for mitosis Produces ribosomes Responsible for protein synthesis Is roughly 10% of the cell’s volume

Nuclear Envelope The nuclear envelope is a highly regulated membrane barrier that separates the nuclear from the cytoplasm in a eukaryotic cell. Contains a large number of different proteins that have been added to the Chromatin organization and gene regulation. The Nuclear Envelope keeps the contents of the nucleus, called the nucleoplasm, separate from the cytoplasm of the cell. The important genetic material, mainly the DNA is kept separate and safe from chemical reactions taking place in the cytoplasm. It is important to keep the DNA protected from the cytoplasm so there is no genetic mutations to the DNA.

Chromosomes Definition: a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes. Has 23 pairs Made up of DNA Can be seen under microscope Ensures DNA is copied correctly

Nucleolus The nucleolus is a spherical collection of fibers and granules made of chromatin within the nucleus and is not separated from the rest of the nucleus responsible for the production of the subunits that form ribosomes,(ribosomes are crucial for creating proteins.) Facilitates transcription of ribosomal RNA. May be responsible for other functions such as detecting cell stress and cell aging.

Genetic Central Control Controls the hereditary characteristics of an organism Contains genes: a short section of DNA, an individual unit of heredity They carry genetic information from one generation of cells to the next Each gene codes for a specific protein by specifying the order in which amino acids must be joined together The genetic information provides codes for embryonic, fetal, childhood and adult growth and development Humans have about 20,000-25,000 genes Humans have approximately the same set of genes, but each individual has slightly different versions of those genes and even more or fewer copies of some genes (this creates uniqueness)

Sources https://micro.magnet.fsu.edu/cells/nucleus/nucleolus.html http://biology.tutorvista.com/animal-and-plant-cells/nucleus.html http://www.uniprot.org/locations/SL-0188 http://www.nature.com/scitable/topicpage/chromosomes-14121320 https://www.genome.gov/26524120/chromosomes-fact-sheet/ http://www.nchpeg.org/nutrition/index.php?option=com_content&view=article&id=4 05