Question

What is the function of vesicles in the synthesis of proteins and the release of those proteins outside the cell?

Answer 1

Vesicles act as containers which carry the proteins from where they are produced (rough endoplasmic reticulum) to the plasma membrane for release.

Explanation:

Proteins produced by ribosomes on the rough endoplasmic reticulum (RER) either embed in to membranes (integral membrane proteins) or enter the lumen of the RER. The latter proteins can then be transported within vesicles, which bud off from the RER.

Vesicles are transported along the cytoskeleton. Those which contain proteins to be secreted travel, via the golgi body, to the internal surface of the plasma membrane.

The vesicle membrane fuses with the plasma membrane, releasing the contained proteins into the extracellular space.