PHSL3211 Lecture Notes - Lecture 1: Pulmonary Circulation, Pacemaker Potential, Sodium-Potassium Alloy
Document Summary
To provide the tissues of the body with an adequate supply of oxygen. To transport all of these substances + others (hormones etc) by bulk flow because diffusion is not enough as we are too big. Cvs = the heart, blood vessels, 4-6l of blood. Reasons for having a double pump (ie for pulmonary circulation): Lungs do not have to compete with systemic circulation for blood flow. Low energy circuit as the lungs are close to the heart thus low resistance to flow. Nb: lungs (bronchi) also receive blood supply from the systemic circulation (bronchial arteries) Parallel circuit: the total resistances of the capillary beds arranged in parallel is much lower than arranged in series, and blood flow to individual organs can be independently controlled (2 exceptions: splanchnic and renal circulation in series) During moderately vigorous exercise, co can quadruple (around 5. 8l/min to 20l/min)
