KINESIOL 1A03 Lecture Notes - Lecture 36: Varicose Veins, Cardiac Output, Pulse Pressure
Document Summary
Blood vessels delivery system of dynamic structures that begins and ends at heart arteries: carry blood away from heart capillaries: contact tissue cells and directly serve cellular needs veins: carry blood towards heart. Capillaries three structural types: continuous capillaries fenestrated capillaries sinusoidal capillaries (sinusoids) Capillary blood pressure ranges from 35 mm hg at beginning of capillary bed to ~17 mm hg at the end of the bed low capillary pressure is desirable because: Ii. high bp would rupture fragile, thin-walled capillaries most capillaries are very permeable, so low pressure forces filtrate into interstitial spaces. Maintaining blood pressure: main factors influencing blood pressure: cardiac output (co) peripheral resistance (pr) blood volume. Forces across a capillary wall capillary hydrostatic pressure (hpc) (capillary blood pressure) tends to force fluids through capillary walls is greater at arterial end (35 mm hg) of a bed than at the venule (17 mm hg)