<prompt> Which of the following are intracellular events occurring in fibroblast during synthesis of collagen-Hydrolysis of procollagen to collagenGlycosylation of prolineFormation of triple helixFormation of covalent cross link bw fibrils  <response>: Formation of triple helix of pre-a-chains takes place intracellularly in RER.Formation of a cross-link between fibrils i.e. self-assembly of tropocollagen monomers into mature collagen fiber occurs extracellularly after secretion from fibroblasts.Glycosylation also occurs intracellularly, but its glycosylation of hydroxylysine not of proline. 