BIOL 341 Chapter Notes - Chapter 20: Osteogenesis Imperfecta, Intermediate Filament, Basal Lamina
Document Summary
Tissues = group of cells (and matrix) performing a similar function. Plant cells don"t have intermediate filaments: cells secrete a cell wall containing cellulose and/or pectin = polymers of sugars and other small molecules. Microtubules in the plant cell determine the orientation of the cellulose microfibrils. Plants: cell walls composed of cellulose, pectin, lignin, etc, cell walls for strength plants lack intermediate filaments in cytosol. Animals: connective tissues (bone, cartilage, etc. ) are predominately extracellular matrix, ecm largely secreted from fibroblasts or osteoblasts, chondroblasts, ecm composed of, structural proteins: e. g. , collagen & elastin, proteoglycans: polysaccharides linked to proteins, adhesive proteins: e. g. , fibronectin and laminin. Bone and cartilage have extensive ecm, but in different forms. Collagen: major component of skin, cornea, tendons, ligaments, cartilage, bone, 25 different a-chains, form different types of collagen from large fibers, to small delicate threads (vary by tissue, most abundant protein in body.
