In oxyhemoglobin dissociation curve, the 95°/a oxygen saturation corresponds __________ oxygen tension in arterial blood
**Core Concept**
The oxyhemoglobin dissociation curve is a graphical representation of the relationship between the partial pressure of oxygen in arterial blood and the percentage saturation of hemoglobin with oxygen. This curve is essential in understanding how changes in oxygen tension affect the binding of oxygen to hemoglobin, thereby influencing tissue oxygen delivery.
**Why the Correct Answer is Right**
At 95% oxygen saturation, the curve starts to plateau, indicating that the hemoglobin is nearly fully saturated with oxygen. This corresponds to a partial pressure of oxygen (pO2) of approximately 60 mmHg. The plateau region of the curve represents the point at which the hemoglobin is fully saturated with oxygen, and further increases in pO2 do not result in significant increases in oxygen saturation. The critical aspect of this plateau is that it occurs at a relatively low pO2, indicating that hemoglobin is still able to bind and transport oxygen effectively at low oxygen tensions.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not accurately reflect the pO2 at 95% oxygen saturation. Options A would imply a significantly higher pO2, which is not consistent with the oxyhemoglobin dissociation curve.
**Option B:** This option is incorrect because it suggests a pO2 that is too low for 95% oxygen saturation. Options B would imply that the hemoglobin is not fully saturated with oxygen at this point, which contradicts the plateau region of the curve.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the oxyhemoglobin dissociation curve is a graphical representation of the relationship between pO2 and oxygen saturation, and it's crucial to understand the plateau region, which indicates the point at which hemoglobin is fully saturated with oxygen.
**Correct Answer:** C. 60