BIOL 221 Lecture Notes - Lecture 4: Medulla Oblongata, Vasomotor Center, Cardiac Output
Document Summary
Elasticity does not directly figure into the poiseuille"s equation, but it does affect the ability of vessels to change to stretch and recoil. Things that are fast-acting can be controlled in the short term are used to regulate bp from minute to minute. Things that are slow-acting are not useful for rapid control of bp but affect bp in the long term. Characterize the following as fast- or slow-acting factors affecting blood pressure: vessel diameter, blood viscosity, total vessel length, vessel elasticity, blood volume, cardiac output. Short-term control of blood pressure is based on controlling resistance by controlling blood vessel diameter and by controlling cardiac output by controlling heart rate and, to a lesser extent, stroke volume. Control of cardiac output was covered in topic 2. Goals of control are to maintain mean arterial pressure (map) to maintain flow throughout the circulation and to alter distribution of blood to meet the varying demands of organs and tissues.