DESCRIBE THE NATURE AND FUNCTION OF EXTRACELLULAR MATRIX (ECM) COMPONENTS, INCLUDING PROTEOGLYCANS AND FIBROUS PROTEINS QUESTIONS WITH 100% CORRECT ANSWERS!!

what is the ECM? - Answer-the non-cellular component present within all tissues and organs what is the ECM composed of? - Answer--composed of collagen I and elastin -fundamentally composed of water, proteins and polysaccharides -a complex network of proteins and polysaccharides what is the ECM secreted by? - Answer-secreted locally by cells and remain closely associated with them what does the ECM provide? - Answer--provides structural, adhesive and biochemical signalling support -not only tissue-specific, also markedly heterogeneous what are the 2 main types of ECM? - Answer-interstitial connective tissue matrix and basement membrane what does interstitial connective tissue matrix do? - Answer-surrounds cells and provides structural scaffolding for tissues what does the basement membrane do? - Answer-separates the epithelium from the surrounding stroma where is the ECM found? - Answer--bone -tendon -cartilage-blood vessel walls -vitreous body of the eye -cornea -dermal layer of skin -basement membrane what is the function of the ECM? - Answer--provides mechanical and structural support -tensile strength -determines cellular microenvironment: surrounds the cell and therefore influences the function and behaviour of the cell >anchors cells (through cell-ECM junctions) >strongly influences embryonic development >provides pathways for cellular migration (e.g wound repair) >sequesters growth factors >provides a residence for roaming phagocytic cells >establishes and maintains stem cell niches what is the composition of the ECM? - Answer--the acellular component of a tissue -5 classes of macromolecules: >collagen >elastin >proteoglycans >hyaluronan (a glycosaminoglycan) >other glycoproteins