The plateau portion of the O?-Hb curve
A)is in the blood- $\mathrm { P } _ { \mathrm { O } _ { 2 } }$ range that exists at pulmonary capillaries
B)means that Hb becomes nearly saturated in the lungs unless pulmonary capillary $\mathrm { P } _ { \mathrm { O } _ { 2 } }$ falls below 60 mm Hg
C)is in the blood- $\mathrm { P } _ { \mathrm { O } _ { 2 } }$ range that exists at the systemic capillaries
D)is both a and b
E)is both b and c

Question

Quizplus · Accepted Answer

The plateau portion of the O₂-Hb curve refers to the range of blood partial pressure of oxygen ($\mathrm { P } _ { \mathrm { O } _ { 2 } }$) where hemoglobin (Hb) becomes nearly fully saturated with oxygen, which occurs in the lungs (choice A). This means that unless the pulmonary capillary $\mathrm { P } _ { \mathrm { O } _ { 2 } }$ falls below 60 mm Hg, Hb will remain almost fully saturated (choice B). At the systemic capillaries, the $\mathrm { P } _ { \mathrm { O } _ { 2 } }$ is lower, and the O₂-Hb curve becomes steeper, allowing for oxygen unloading to the tissues (choice C). Therefore, both choices A and B are correct, making choice D the best answer.

The Plateau Portion of the O?-Hb Curve A)is in the Blood-

The Plateau Portion of the O?-Hb Curve
A)is in the Blood-