What type of proteins do 'free' ribosomes in the cytosol manufacture? I know ribosomes studded on the Rough E.R manufacture tertiary level proteins?
Also, does the E.R secrete its contents for the cell or for external cells? Can someone clarify this please? Thanks!
Free ribosomes are the site of protein synthesis, for proteins that carry out their biological function within the cells they are produced. Ribosomes studded on the endoplasmic reticulum, which forms the rough endoplasmic reticulum organelle, synthesise proteins that carry out their biological function outside the cell in which they are produced.
The endoplasmic reticulum is an organelle made up of a network of membranous sacs, transporting substances within the cell and also partially modify the substances transported within the cell. It is the golgi apparatus that packages synthesised materials into vesicles that bud off the golgi body, and transport the synthesised materials out of the cell by exocytosis.