软骨和骨组织学和胚胎学.pptx

Cartilage and Bone 1.Cartilage:organ=Cartilage tissue+perichondrium 1)structure of cartilage tissue -cell:chondrocyte -cartilage matrix chondrocyte:-Structure:LMembedded in cartilage lacunaperipheral cells:-small and immature -single and flattenedcentral cell:-large and mature,-round and in group of 2-8 cells -small and round nucleus -basophilic cytoplasm -EM:rich in RER and Golgi complex*isogenous group:several cells locates in one lacuna,which are derived from a single(same)parent cell Cartilage matrix-ground substance:proteoglycan:-same to loose CT -there are more chondroitin sulfate distributed at the periphery of cartilage lacuna-called as cartilage capsule(basophilic)water-fiber:type and number of fiber depends on the type of cartilage2)Classification:according to the fibera.Hyaline cartilage:less collagenous fibrilarticular surface,rib cartilage,trachea and bronchib.Fibrous cartilage:large amount of collagenous fiber bundles cells are small and lessintervertebral disc,symphysis pubisc.Elastic cartilage:large amount of elastic fiberexternal ear,epiglottis3)perichondriumtwo layers:-out layer:contain more fiber-protection -inner layer:more cells-osteoprogenitor cell(fusiform in shape)4)growth of cartilage-interstitial growth:inner chondrocyte proliferation produce fiber and matrix.immature cartilage-appositional growth:osteoprogenitor cellchondroblast chondrocyte produce fiber and matrix.growing and mature cartilage2.Bone-consists of bone tissue,periosteum and endosteum,bone marrow1)Bone tissue Cells:a.osteoprogenitor cell:stem cell-structure:fusiform,small ovoid nucleusslight basophilic cytoplasmexist in periosteum and endosteum-function:differentiated into osteoblast and chondrocyteb.osteoblast:-structure:LM:single layer of cuboidal or low columnar cellround nucleusbasophilic cytoplasmlocated on the surface of bone tissueEM:fine processesrich in RER,Golgi complex-function:.synthesize bone collagen fiber and ground substance-osteoid.release matrix vesicle:0.1um in diameter membrane-coated function:promote calcificationc.osteocyte-structure:flattened cell with multiple long thin processeslocated in bone lacuna and bone canaliculusbasophilic cytoplasmadjacent cells connect in bone canaliculus by gap junctions-function:Maintain bone matrixd.osteoclast-structure:LM:multinuclear large cell,30-100um 6-50 nuclei acidophilic cytoplasm located at peripheral part of boneEM:ruffled border-processes light zone:-under the ruffled border -microfilament primary lysosome,pinosome and secondary lysosome RER,mito.and Golgi-function:dissolve and absorb bone matrixBone matrix-organic matter:bone collagen fiber-collagenous fiber(type I collagen)ground substance:glycosaminoglycan-inorganic matter:bone saltsHydroxyapatite crystal:Ca10(PO4)6(OH)2 pin-shaped longitudinal arranged*bone lamella:bone matrix arranged in layers at different direction2)Architacture of long bone Long bone is an organ,made up of bone tissue(shaft and epiphyses),periosteum and endosteum,bone marrow shaft:consists of compact bone a.circumferential lamella:/outer concentrically-arranged /inner around inner surface of bone b.Haversian system(osteon):/cylindric structure,3-5mm /central canal:N,BV,CT /Haversian lamella:4-20 layersc.interstitial lamella:/irregular lamella /remnant of Haversian or circumferential lamella*perforating canal:/transverse canal /connect with Haversian canal epiphyses:composed of spongy bone-trabeculae:formed by parallelly-arranged lamellaform a spongy-liked network-Bone marrow:hemopoietic tissue periosteum and endosteum:CT membrane-periosteum:DCTouter layer:more fiber bundles form perforating fiberinner layer:rich in BV,N and osteoprogenitor cells-endosteum:thin,a layer of osteoprogenitor cell and CT-function:provide nutrition and osteoblast for bone growth and repairing 3)osteogenesis Self study!