组织学与胚胎学Connective Tissue1.ppt

Nails Chapter 3. Connective Tissue Today’s points 7 types of cell in Loose Connective Tissue The procedure of collagen fiber synthesis 1. Introduction 1.1 Connective tissue (CT) comprises a diverse group of cells embedded in a tissue-specific extracellular matrix. All of CTs originate from mesenchyme embryonic CT 1.2 Component 1.3 Classification Three general types A. Connective tissue proper B. Fluid connective tissue C. Supporting connective tissue 1.4 Characteristics A. Have small number of cells but have much extracellular matrix. B. The cells in connective tissue have no polarity, and they are widely separated in the extracellular matrix. C. Have no basement membrane, but have blood vessel and nerve. 1.5 Function Establishes a structural framework for the body Transports fluids and dissolved materials Protects delicate organs Supports, surrounds and interconnects other tissue types Stores energy reserves, esp. lipids Defends body against foreign microbes In a word, CT have functions of connecting, supporting, protecting, nutrition, defense and repairing 2. Connective tissue proper 2.1 Loose connective tissue there are 7 types of cells present in LCT Fibroblast, Macrophage, Plasma cell, Mast cellFat cell, undifferentiated mesenchymal cell ,Leukocytes. ① fibroblast EM: rich in RER, Golgi appatatus and free ribosome ---function: synthesize fibers and ground substance Synthesis of collagenous fiber in three steps: a. synthesis of procollagen (RER) → process (Golgi) → procollagen → 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 Small and dark nucleus Acidophilic cytoplasm EM: rich in a.??lysosome b. Phagosome← phagocytosis