Mechanisms used in the transport of gases (O2 and CO2) in the blood Chemical rea
ID: 176592 • Letter: M
Question
Mechanisms used in the transport of gases (O2 and CO2) in the blood Chemical reactions involved in the transport of oxygen and carbon dioxide within blood Understand the oxygen-hemoglobin curve as it relates to the ability of hemoglobin to be saturated with oxygen at different partial pressures Importance of small changes vs large changes in partial pressure with respect to the effects of these changes in altering the saturation of hemoglobin with oxygen How is this curve affected under various circumstances (i.e.. pH change/Bohr effect, altitude change)? Why does it have "sigmoidal" versus a "straight line" shape?Explanation / Answer
1. Factors that affects the Oxygen Dissociation Curve are.
pH, Temperature, CO2
Increased pH:
Decreased pH:
There is no clinically significant change in hemoglobin’s ability to transport oxygen from the lungs to the rest of the body’s tissues and cells.
However, if the partial pressure of oxygen is abnormally low, even small shifts in the curve can significantly affect hemoglobin’s ability to pick up and release oxygen at the tissue level.
The Straight portion of the curve shows that the partial pressure of oxygen in the blood can fall from 100 to 60 mm Hg and the hemoglobin will still be 90% saturated with oxygen.
The Sigmoidportion of the curve shows that the reduction of partial pressure of oxygen below 60 mm Hg produces a rapid drop in the percent of hemoglobin saturated with hemoglobin (SaO2).
As the partial pressure falls below 60 mm Hg, which typically correlates with a saturation level of less than or equal to 90%, the amount of oxygen being delivered to tissues and cells may be significantly decreased.