cell bio question

[joonkimdds]

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for molecules to be secreted from the cell, which of the following is the most likely pathway for movement of the molecules in the cell?
a) Goldgi => ER=>lysosome
b) Nucleus =>ER=>golgi
c) ER=>Golgi => vesicles that fuse with the plasma membrane

I think all of them are correct but there is only 1 answer.
I think endomembrane system goes from
nucleus=>ER=>golgi=>lysosome=> vesciels that fuse with plasma membrane.
can u tell which one is correct?

 

[Muzikman712]

I think the answer is definitely C. Molecules to be secreted from the cell are assembled on rough E.R., modified (e.g. glycosylation, additional protein folding, etc) and packaged as it moves through the golgi apparatus through budding and fusing w/ golgi membranes, and finally leaves the trans surface of the golgi to be packaged into secretory vesicles which migrates towards the plasma membrane, fusing with it and releasing the molecule. If the molecule were to go to the lysosome after the golgi it would be broken down by hydrolytic enzymes and not be secreted. Molecules entering the cell though first fuse with endosomes, which then fuse with lysosomes to be broken down. Hope that helps...