e03.Connective tissue结缔组织.ppt

组织胚胎学课件 七年制英文医学班专用  Chapter 3  Connective tissue 1.?????? General features: 1)???small number of cells and large amount of extracellular ground substance 2)? extracellular is composed of fibers and amorphous ground substance-matrix 3)???all of them originate from mesenchyme-embryonal CT 4) have functions of connection, supporting, protecting, nutrition, defence and repairing mesenchyme ---mesenchymal cell: /structure: stellate in shaped with processes a large nucleus,with clear nucleoles slight basophilic cytoplasm /function: a.??? undifferentiated cell b. multiple developmental potential→CT cell, SM and endothelial cell ---matrix 2.?????? Classification ---CT in narrow sense means connetive proper which include loose CT, dense CT, adipose T and reticular tissue ---CT in wide sense includes cartilage, bone and blood 3.??Loose connective tissue(areolar tissue) features: have more types of cells and less fibers functions: connection,supporting,defence and repairing consists of cells, fiber and ground substance cells: seven types of cells are present in LCT ① fibroblast ---structure: LM: large,flattened cell with processes- stellate in shaped Large ovoid pale nucleus-contain more fine chromatin, with clear one-two nucleoli Weakly basophilic cytoplasm-homogeneous EM: rich in RER,Golgi appatatus and free ribosome ---function: synthesize fibers and ground substance Synthesis of collagenous fiber Three steps: a.synthesis of procollagen(RER) → process(Golgi) → out of cell b.procollagen→ tropocollagen → fibril c.fibril → collagenous fiber *fibrocyte: still state or inactive fibroblast ---structure: spindle-shaped, small N:small,dark stained Acidophilic cytoplasma EM: less organelles ---function: become into fibroblast for repairing ②macrophage ---structure: LM: round or ovoid-irregular in shape when it have sho