Nucleus+and+substructures

Nucleus and substructures
Nucleus -
 * membrane-enclosed organelle found in all eukaryotic cells
 * contains most of the cell's genetic material
 * organized as multiple, long DNA molecules
 * regulates all cell activity
 * controlls the present enzymes

Nucleolus -
 * also called nucleole
 * non-membrane bound structure
 * found within nucleus
 * composed of proteins and nucleic acids
 * contains most genes(RNA)
 * synthesizes the RNA



** Nuclear Envelope and Nuclear Pores**
 * [|Nuclear Envelope] surrounds the nucleus of eukaryotic cells
 * 2 membranes composed of phospholipids
 * The outer membrane consists of ribosomes and is continuous with the rough endoplasmic reticulum so that DNA messages can turn into RNA and then protiens
 * The inner membrane is connected to the outer membrane by the lumen, or the intermembrane space
 * The nuclear envelope contains several pores that help regulate the flow of macromolecules entering and exiting the cell
 * Each nuclear pore is about 70nm and is surrounded by protein

[|http://www.daviddarling.info/encyclopedia/N/nuclear_envelope.html] ** __**http://en.wikipedia.org/wiki/Cell_nucleus**__ __**http://commons.wikimedia.org/wiki/Image:Diagram_human_cell_nucleus.svg**__
 * Sources