Final answer:
The pathway for a protein destined for secretion is ribosome synthesis, ER modification, Golgi tagging, and vesicle distribution, with the final step being secretion outside the cell via vesicle fusion with the plasma membrane.
Step-by-step explanation:
The correct pathway for a newly synthesized protein destined for secretion from a eukaryotic cell is initiated at the ribosome, where the protein is synthesized. From there, it is targeted to the endoplasmic reticulum (ER) for modification. Upon proper folding and modification, the protein is then transported to the Golgi apparatus in a vesicle, where it undergoes further processing and tagging. Once this is complete, the protein is packaged into secretory vesicles that bud from the trans face of the Golgi. These vesicles can either deposit their contents within the cell or they can fuse with the plasma membrane, leading to secretion of the protein outside the cell.
Given the options listed in the student’s question, the most accurate description of the protein secretion pathway is: 'synthesis of the protein on the ribosome; modification in the endoplasmic reticulum; tagging in the Golgi; distribution via the vesicle.'