BIOM20001 Lecture Notes - Lecture 37: Basal Lamina, Ground Substance, Fibril
Document Summary
37 integrating cells into tissues ii: extracellular matrix proteins. Connective tissue has large amount of extracellular matrix (ecm) Basal lamina is a special form of emc. Spaces between cells composed of a complex array of molecules. Composed of tough fibrous proteins embedded in a polysaccharide gel-like material called ground substance. Variety in connective tissues due to differences in composition and arrangement of ecm: Tendon numerous fibrous proteins, little ground substance (little ability to resist compressive forces) Regulation of cellular activities: survival, migration, proliferation, shape, function. Cells produce and secrete organic components of ecm. Collagen fibres must be correctly aligned within tissues. Chick heart cells plated on collagen layer bind to collagen fibres, provide tension, causes collagen fibres to align. Cells that produce ecm- vary from tissue to tissue: Lens epithelial cells produce one of the thickest basement membranes in the body the lens capsule. Rich in proline and glycine arranged in repeats as a helical polypeptide chain.
