Can you trace the path of protein out of the cell?

Question

mentioning and explaining nucleus, rough er, smooth er, golgi apparatus, and exoctytosis!

Answer 1

.A protein for export will have a signal protein that will associate with an SRP (SEE below for SRP cycle)

that will halt synthesis, from the mRNA produced by transcription in the nucleus, until it comes in contact with rough ER docking site and translation will resume.  The signal peptide will be cleaved with signal peptidase.  Then the protein will be brought to the cis-side of the Golgi via transitory vesicles where it will be further processed.  The protein probably binds to a receptor side on the trans side of the Golgi and a secretory vesicle is formed with the protein inside.  The secretory vesicle moves towards the plasma membrane where it fuses with the membrane, the protein is released and the secretory vesicle membrane becomes part of the plasma membrane.(exocytosis)

http://cr.middlebury.edu/biology/SCB2-de...

The SRP cycle

The signal recognition particle (SRP) associates with ribosomes  that are in the process of translating the mRNA  for a secretory protein. The protein has a signal at the N-terminus. Subsequently, the ribosome-bound SRP interacts with the SRP-receptor, a component of the ER membrane. Finally, SRP recycles to associate with another ribosome, and translation continues with the secretory protein transversing the membrane through a channel called the translocon and entering the lumen of the rough ER.

http://bio.lundberg.gu.se/dbs/SRPDB/Stru...