<prompt> True statement regarding insulin:Produced by alpha cells of pancreasTwo polypeptide chains are bound by disulfide linkagesShifts potassium outside the cellS.c insulin tl2 is 60 mins  <response>: Ref: Harpers Illustrated Biochemistry,28th editionExplanation:InsulinSecreted from pancreatic islet b cellsReleased regulated by blood glycemic thresholdSynthesized as a single chain : pro-insulinInsulin is formed from proinsulin removal of the connecting or C peptideInsulin is thus made up of 2 chainsA 21 amino acids and B 30 amino acidsConnected to each other by 2 inter disulfide bridges and 1 intra disulfide bridgeAll necessary for its hormone activity.ActionsStimulates glucose oxidation storage and inhibits glucose productionStimulates glycogen synthaseInhibits phosph orylaseInhibits gluconeogenesisStimulates glucose transport into adipocytes, which is then converted intoTGInhibits hormone-sensitive lipase HPL cAMP and lipoprotein lipaseActivates GLUT1Stimulates fatty acid and triglyceride synthesisInhibits I i poly sis and proteolysisShifts potassium ions from ECF to ICF 