Cell Biology: Cellular Compartments Part II

NUCLEUS

• Structure
• Nuclear Envelope made up of two phospholipid bilayer membrane
• Inner nuclear membrane is around nucleus itself
• Outer nuclear membrane is continuous with the rough ER
• The two membranes fuse at nuclear pores
• nuclear pores = ringlike complexes composed of specific membrane proteins through which material moves between the nucleus and the cytosol
• Nuclear Matrix
• Made of fibrous proteins called lamins which form a TD network along the inner surface of the inner membrane, giving it shape and apparently binding DNA to it.
  
• Functions
• Replicates DNA
• Syntehsizes rRNA, tRNA, and mRNA