The Chemical Reactions and Pathways Resulting in the Formation of Collagen Any of a Group of Fibrous Proteins of Very High Tensile Strength That Form the Main Component of Connective Tissue in Animals. Collagen Is Highly Enriched in Glycine (some Regions Are 33% Glycine) and Proline Occurring Predominantly As 3 Hydroxyproline (about 20%).
The Irregular Network of Unit Membranes Visible Only by Electron Microscopy That Occurs in the Cytoplasm of Many Eukaryotic Cells. the Membranes Form a Complex Meshwork of Tubular Channels Which Are Often Expanded Into Slitlike Cavities Called Cisternae. the Er Takes Two Forms Rough (or Granular) with Ribosomes Adhering to the Outer Surface and Smooth (with No Ribosomes Attached).