BIO 282 Lecture 27: Respiratory Physiology Continued 3
Document Summary
So that there can be a reserve for oxygen a) Basically just in case the need for oxygen goes up c) Basically just in case the need for oxygen goes up. The po2 in alveoli an tissues + he o2-hb binding curve ultimately impacts how much oxygen is delivered to the tissues in the systemic circuit. Systemic circuit is blood being pumped from heart to tissues. Pulmonary circuit is blood being pumped from tissues to heart. Since the po2/pco2 in our alveoli does not equal atmospheric po2/pco2, as we go up to extremely high altitudes, delivering sufficient o2 to tissues becomes a challenge/physiological stressor that our bodies work to respond to. But thanks to the hemoglobin-o2 curve shape, we"re okay at lower altitudes of < 3500 m. % hb saturation is very sensitive to changes in po2 in the lower range. % hb saturation is relatively insensitive to changes in po2 in the higher range.
