Functions of large A 1. transport blood from heart 2. store blood during ventricle contraction 3. elastic recoil keep continuous blood flow
Functions of large A. 1.transport blood from heart 2.store blood during ventricle contraction 3.elastic recoil keep continuous blood flow
Small artery and arteriole muscular A Struetural characters 1. Diameter<lmm 2. Present internal elastic lamina 3. A few layers of smooth muscle F 4. No external elastic lamina 5. Arteriole: diameter <0.3mm 1-2lavers of smooth muscle F Functions regulate blood pressure
Small artery and arteriole muscular A. Structural characters 1.Diameter<1mm 2. Present internal elastic lamina 3. A few layers of smooth muscle F. 4. No external elastic lamina 5.Arteriole: diameter < 0.3mm 1~2layers of smooth muscle F. Functions 1. regulate blood flow to organs and tissues 2. regulate blood pressure
Comparison LA MA SA Internal elastic lamina not evident evident present dia elastic laminas SMf, SMF external elastic lamina not evident evident absent another name elastic a muscular a function
Comparison LA MA SA Internal elastic lamina not evident evident present media elastic laminas S.M.F. S.M.F. external elastic lamina not evident evident absent another name elastic A. muscular A. function
Capillary T A diffuse network of thin tubules between A. and k. 毛细血管 the main place for substance interchange
Capillary A diffuse network of thin tubules between A. and V. the main place for substance interchange
Characters 1. distribution(everywhere)--m--very wide total length(60,000 km)------very long total area(6000 m2)-----------very large 2. lumen(6-8um) very narrow 3. blood current-----------------very slow 4. wall -- very thin
Characters 1. distribution (everywhere) -----very wide total length (60,000 km) ------very long total area(6000 m2 )------------very large 2. lumen (6~8μm) ------------very narrow 3. blood current-----------------very slow 4. wall --------------------------- ? very thin