In __________, messenger RNA is first transcribed on the DNA template

(1). After processing within the nucleus

(2), the mRNA leaves the nucleus through nuclear pores

(3). The synthesis of intracellular proteins

(4) is accomplished by polysomes, which consist of molecules of mRNA associated with ribosomes. Synthesis of proteins for export from the cell is accomplished on the rough endoplasmic reticulum

(5). From there they are transported

(6) to the Golgi apparatus

(7), where they may be complexed with newly synthesized polysaccharides. Small membrane-bound vesicles containing the proteins leave the Golgi apparatus

(8) and, when they reach the cell membrane

(9), fuse with it and release the protein molecules by a process called exocytosis

Review: EMBRYOL Chapter 1 - Embryology: History and Concepts