PEDS200 Lecture : Gas Exchange

• School: University of Alberta
• Department: Physical Education and Sport
• Course: PEDS200
• Professor: Dan Syrotuik

Document Summary

Partial pressure: atmospheric pressure x concentration of gas. Henry"s law: amount gas dissolved in fluid depends on pressure difference between air and fluid, and solubility of gas: p is driving force for diffusion, how much gas is taken up depends on solubility. At tissue arterial o2 diffuses into tissue and co2 diffuses out of tissue. A-vo2 difference: difference in o2 content between arterial and mixed venous blood: represents o2 extraction @ tissue level per 100ml blood, rest 5. 0ml/100ml blood, max exercise 15ml/100ml blood. Co2 more soluble than o2, transported by: dissolved in plasma, combined with hb, combined with h20 to form bicarbonate (used most) Majority of o2 transported via hb, ~1. 34mlo2/g hb: males higher hb concentration, o2 carrying capacity= [hb] x 1. 34. During exercise, hemoconcentration occurs as plasma shifts from blood to working tissues, through sweat loss: incr. During exercise curve shifts down and to right: %sao2 decreases because (bohr effect), incr. O2 unloading at tissue level, incr. a-vo2 diff.