Block 2b Gas Transport

Question 1

Venous PO2

Answer 1

40 mmHg

Question 2

Alveolar PO2

Answer 2

104 mmHg

Question 3

Arterial PO2

Answer 3

95 mmHg

Question 4

Interstitial PO2

Answer 4

40 mmHg

Question 5

Intracellular PO2

Answer 5

23 mmHg

Question 6

When does Hb dissociation curve become steep?

Answer 6

below 40 mmHg O2

Question 7

What is the utilization coefficient?

Answer 7

the percentage of blood that gives up its O2 in capillaries

Question 8

What is the normal utilization coefficient?

Answer 8

25%

Question 9

What factors cause a right-shift in the Hb dissociation curve?

Answer 9

H+, CO2, T, BPG

Question 10

What is the Bohr effect?

Answer 10

effect of H+, CO2, T, & BPG to favor O2 dissociation at higher PO2

Question 11

How does affinity of Hb for CO compare to that of O2?

Answer 11

250x

Question 12

Intracellular PCO2

Answer 12

46 mmHg

Question 13

Interstitial PCO2

Answer 13

45 mmHg

Question 14

Venous PCO2

Answer 14

45 mmHg

Question 15

Arterial PCO2

Answer 15

40 mmHg

Question 16

Alveolar PCO2

Answer 16

40 mmHg

Question 17

How is CO2 transported in blood?

Answer 17

1) soluble, 2) carbaminohemoglobin 3) HCO3- product of CA

Question 18

What percentage of CO2 is transported via HCO3- product of CA?

Answer 18

70%

Question 19

What percentage of CO2 is transported via carbaminohemoglobin?

Answer 19

23%

Question 20

What is the haldane effect?

Answer 20

binding of O2 displacing CO2 from Hb

Question 21

What is the chloride shift?

Answer 21

HCO3- exchanged for Cl- in RBC via SLC4A1 transporter

Question 22

What are the determinants of interstitial PCO2 & PO2?

Answer 22

blood flow & metabolism

Question 23

What is the O2 content of blood?

Answer 23

20 mLO2 /dL