Chapter 6 Muscular Tissue
Chapter 6 Muscular Tissue
1. General description 1)components cell: muscle fiber-myofiber c elongated thread-liked e Sarcolemma e Sarcoplasm e sarcoplasmic reticulum SER --extracellularG.S: CT with bV.LV and n
1. General description 1) components: ---cell: muscle fiber-myofiber elongated thread-liked Sarcolemma Sarcoplasm sarcoplasmic reticulum: SER ---extracellular G.S: CT with BV, LV and N
2) classification According to the structure and function skeletal muscle: striated, voluntary s cardiac muscle: striated, involuntary e smooth muscle: unstriated, involuntary
2) classification According to the structure and function skeletal muscle: striated, voluntary cardiac muscle: striated, involuntary smooth muscle: unstriated, involuntary
2 Skeletal muscle
2. Skeletal muscle
Muscle is an organ consists of muscle fiber and ct, fixed on bone by tendons CT 肌原纤维 肌纤维 肌纤维 肌束膜 肌内膜 肌内膜 肌束膜 肌膜 我肌细胞核 成纤维 肌上膜 S epimysium DCT Perimysium ● Endomysium e muscle satellite cell: differentiate and proliferate function: supporting, connecting, nourishing and regulating
Muscle is an organ, consists of muscle fiber and CT, fixed on bone by tendons CT: epimysium: DCT Perimysium Endomysium muscle satellite cell: differentiate and proliferate function: supporting, connecting, nourishing and regulating
1) microstructure of skeletal muscle fiber O long cylindrical 10-100um in diameter, 1-40mm long 2 multinucleate, nuclei are ovoid distributed under sarcolemma 8 filled with long itudinal parallel-arranged myofibrils
1) microstructure of skeletal muscle fiber ① long cylindrical 10-100um in diameter,1-40mm long ② multinucleate, nuclei are ovoid, distributed under sarcolemma ③ filled with longitudinal parallel-arranged myofibrils
myofibril 1-2um in diameter e cross striation: light band -l(isotropic) band dark band-A(anisotropic)band a band: M-line. H-band i band: Z-line
myofibril: 1-2um in diameter cross striation: light band -I(isotropic) band, dark band- A(anisotropic) band --A band: M-line, H-band --I band: Z-line
教额 sacromere: a/ segment of myfibri extending from one Z line to next Z line, which is composed of 1/2 I band, A band and 1/2 band. is the smallest structural and functional unit of myofibril
* sacromere: a segment of myfibril extending from one Z line to next Z line, which is composed of 1/2 I band, A band and 1/2 I band ,is the smallest structural and functional unit of myofibril
2 Ultrastructure of myofiber ∵··· ① myofibril: composed of thick myofilament: 1.5 um long, 15nm in diameter ● composed of myosin: rob: in bundles 肌动蛋白单体原肌球蛋白 肌原蛋白 In T -head 细肌丝 cross bridge binding (3 site(ATPase activity) 肌球蛋白杆 (横桥)
2) Ultrastructure of myofiber ① myofibril: composed of ---thick myofilament: 1.5 um long, 15nm in diameter composed of myosin: -rob: in bundles -head: cross bridge- binding site(ATPase activity)
thin myofilament e lum long, 5nm in diameter ● composed of: A actin- spherical monomers of globular actin arranged in two row and twisted- filamentous 肌动蛋白单体原肌球蛋白 肌原蛋自 T actin, each monomer has anie OO binding site 肌球蛋白杆 粗肌丝 肌球蛋白头 横桥)
---thin myofilament: 1um long, 5nm in diameter composed of: A. actin- spherical monomers of globularactin arranged in two row and twisted- filamentous actin, each monomer has binding site
