BSC 1086C Lecture Notes - Lecture 8: Carbonic Anhydrase, Haldane Effect, Ph
Document Summary
Oxygen-hemoglobin dissocation curve: hemoglobin saturation plotted against po2, is not linear, s-shaped curve, shows how binding and release of o2 is influenced by the po2. In arterial blood: po2= 100 mm hg, contains 20 ml oxygen per 100 ml blood (20 vol%, hb is 98% saturated, further increases in po2 (e. g. breathing deeply) produce minimal increases in o2 binding. In venous blood: po2= 40 mm hg, contains 15 vol% oxygen, hb is 75% saturated. Factors that increase release of o2 by hemoglobin. As cell metabolize glucose: pco2 and h+ increase in concentration in capillary blood. Declining ph weakens the hemoglobin-o2 bond (bohr effect: heat production increases. Increasing temperature directly and indirectly decreases hb affinity for o2. Influence of po2 on hemoglobin saturation temperature ranges. Hemoglobin is almost completely saturated at a po2 of 70 mm hg. O2 loading and delivery to tissues is adequate when po2 is below normal levels.
