Can you tell me how insulin is made and exported by a pancreatic cell?

Biology: The insulin gene is transcribed to messenger RNA in the nucleus. The mRNA is translated to preproinsulin in the rough endoplasmic reticulum. The N-terminal "pre" peptide is cleaved, the proinsulin is packaged in secretory vesicles and further processed to insulin & C-peptide). Upon stimulation (rising ambient glucose, influenced by other signals), the vesicles fuse with plasma membrane & release I