Systemic venous $\mathrm { P } _ { \mathrm { O } _ { 2 } }$ is ____ alveolar $\mathrm { P } _ { \mathrm { O } _ { 2 } }$
, and systemic venous $\mathrm { P } _ { \mathrm { CO } _ { 2 } }$
Is ____ alveolar $\mathrm { P } _ { \mathrm { CO } _ { 2 } }$ .
A)greater than, greater than
B)greater than, less than
C)less than, greater than
D)less than, less than
E)equal to, equal to

Question

Quizplus · Accepted Answer

Systemic venous blood has already provided oxygen to the body tissues and has taken up carbon dioxide from them. Therefore, its PO2 is lower and PCO2 is higher compared to the alveolar PO2 and PCO2 that reflect the gas exchange process in the lungs. Systemic venous PO2 is around 40 mmHg, while the alveolar PO2 is around 100 mmHg. Systemic venous PCO2 is around 46 mmHg, while the alveolar PCO2 is around 40 mmHg. Therefore, systemic venous PO2 is less than alveolar PO2, and systemic venous PCO2 is greater than alveolar PCO2.

Systemic Venous PO2\mathrm { P } _ { \mathrm { O } _ { 2 } }PO2​​

Systemic Venous $\mathrm { P } _ { \mathrm { O } _ { 2 } }$