BIOL 3113 Lecture Notes - Lecture 22: Scleroprotein, Laminin, Proteoglycan
Document Summary
The cells of multicellular organisms are organized into cooperative assemblies of different levels of complexity: Organs functional structures made of several tissues and cell types. Organ systems groupings of organs that work together to carry out higher order functions. Cells are held together in tissues at two levels: Extracellular matrix - produced and secreted by cells provides the physical framework to which cells are attached. Cell junctions - specialized regions of the cell membrane that are responsible for attaching cells to: extracellular matrix and to each other. Extracellular material, produced by cells, provides structural framework for animal tissues, organs and organisms. The ecm is produced primarily (but not exclusively) by connective tissue cells: fibroblasts ordinary connective tissue, chondrocytes cartilage, osteoblasts bone. *fibrous proteins: collagen - structural, elastin - structural, fibronectin - adhesive, laminin adhesive. The most abundant protein in animals (up to 25% of the total proteins in mammals) and the major component of the ecm.
