Blood Gas Transport

Question 1

What are the different ways that oxygen is carried in the blood?

Answer 1

1. Dissolved

2. Combined with hemoglobin

Question 2

What would the cardiac output have to be in order to solely rely on dissolved O2?

Answer 2

83L/min

Max exercise is only 25-35- L/min

Question 3

What is the structure of hemoglobin?

Answer 3

• Heme- with ferrous ion bound

- Globin- 2 alpha and 2 beta chains

Question 4

How many O2 molecules can bind to one hemoglobin?

Answer 4

4

Question 5

What influences the binding affinity of O2 to hemoglobin?

Answer 5

Already bound O2

Question 6

What is methemoglobin?

Answer 6

This is when the ferrous ion has been converted to the ferric form by drugs or disease. Does not carry O2 very well

Question 7

What is the O2 dissociation curve?

Answer 7

It shows the relationship between the O2 and amount of HbO2

Question 8

What is the typical amount of O2 that Hb can carry?

Answer 8

1.34ml O2/g

Question 9

What is the average concentration of Hb in the blood?

Answer 9

15g Hb/100ml

Question 10

What is typical arterial O2 blood saturation level?

Answer 10

97%

Question 11

What is the typical venous blood O2 saturation level?

Answer 11

75%

Question 12

What is the total amount of O2 in the blood?

Answer 12

19.8 ml O2/ 100ml

Question 13

What is the level of O2 extraction at rest?

Answer 13

25%

Question 14

What is the amount of O2 in venous blood?

Answer 14

15ml O2/ 100ml

Question 15

What is the extra oxygen in venous blood for?

Answer 15

Serves as an extra store of O2 during exercise. It is also why acute HF doesn’t see a large drop of O2 levels

Question 16

What is P50?

Answer 16

This is the PO2 at which 50% of Hb is saturated and can tell us where the rest of the curve will lay

Question 17

What is normal human P50?

Answer 17

27mmHg

Question 18

What can cause P50 to be shifted to the right?

Answer 18

• Exercise= increase temp., lower pH, increase PCO2

- DPG

Question 19

What is the consequence of moving P50 to the right?

Answer 19

It lowers the affinity so offload of O2 is faster

Question 20

What is myoglobin?

Answer 20

This is found in high amount in highly oxidative muscles. It give them their red color. Assists in intracellular of O2. it shifts the O2 dissociation curve to the left

Question 21

How is Carbon dioxide transported?

Answer 21

1. Bicarbonate
2. With proteins
3. Dissolved

Question 22

How is CO2 transported as bicarb?

Answer 22

Carbonic hydrogenase converts CO2 into HCO3- and H+. It travels through the blood like this until it gets to the lungs where it is converted back to CO2 and expired

Question 23

What is Haldane’s effect?

Answer 23

HCO3- made in RBC can easily diffuse out but the H+ stays in. To keep electroneutrality, Cl- and water come in. H+ binds to hemoglobin and increase O2 offload and increases ability to carry CO2

Question 24

What are carbamino compounds?

Answer 24

This is when CO2 binds to an amine group usually globin

Question 25

What gas can you find at a higher dissolved concentration in the blood?

Answer 25

CO2

Question 26

What type of Hb carries the most CO2?

Answer 26

Deoxygenated Hb

Question 27

What is the difference in the Co2 and O2 dissociation curve?

Answer 27

Co2 is much more steep and linear