PHYL2001 Lecture Notes - Lecture 10: Vapor Pressure, Partial Pressure, Total Pressure
Document Summary
Gas fractional [gas]= total number of gas molecules. Partial pressure= pressure that each gas would exert individually. Total pressure= sum of individual gas pressures. Partial pressure of oxygen: water is 47mmhg when you inspire the air it is humidified hence you must take into account the water vapour pressure into account. Constant movement of oxygen and carbon dioxide. When looking at alveolar oxygen, it is just above. The ventilation if sufficient given that we are at rest. The oxygen consumption is 250ml/min which is what our cells use at rest. If we exercise- we increase our demand for oxygen consumption. Hence we need to change our alveolar ventilation and increase it to keep our normal alveolar po2. Alveolar po2 depends on how much the body consumes (rest/exercising) and on the alveolar ventilation (how much it gets into the lungs, and how much is used by the body) Carbon dioxide at rest is slightly lower than the oxygen level at rest.
