文档介绍：组织胚胎学课件 七年制英文医学班专用
中国医科大学
基础医学院
组胚—英文教学组
Chapter 6 Muscular Tissue
1.       General description
1) components:
---cell: muscle fiber-myofiber
elongated thread-liked
Sarcolemma
Sarcoplasm
sarcoplasmic reticulum: SER
---extracellular : CT with BV, LV and N
2) classification
According to the structure and function
skeletal muscle: striated, voluntary
cardiac muscle: striated, involuntary
smooth muscle: unstriated, involuntary
2.    Skeletal muscle
Muscle is an, 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
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
cross striation: light band -I(isotropic) band, dark band- A(anisotropic) band
--A band: M-line, H-band
--I band: Z-line
* sacromere: a segment of myfibril extending from one Z line to next Z line, which posed 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:
um long, 15nm in posed of myosin:
-rob: in bundles
-head:
cross bridge- binding site(ATPase activity)