Oxygen Disasscoiation Curve

Question 1

What does a left shift in the oxygen dissociation curve indicate?

Answer 1

Increased saturation of Hb with oxygen for a given oxygen tension

This results in decreased oxygen delivery to tissues.

Question 2

What does a right shift in the oxygen dissociation curve indicate?

Answer 2

Reduced saturation of Hb with oxygen for a given oxygen tension

This results in enhanced oxygen delivery to tissues.

Question 3

Name three factors that cause a left shift in the oxygen dissociation curve.

Answer 3

• HbF
• Methaemoglobin
• Carboxyhaemoglobin

These conditions lead to increased affinity of hemoglobin for oxygen.

Question 4

What is the effect of low [H+] on the oxygen dissociation curve?

Answer 4

Causes a left shift

Indicates an alkaline environment.

Question 5

What is the effect of low pCO2 on the oxygen dissociation curve?

Answer 5

Causes a left shift

Indicates lower carbon dioxide levels.

Question 6

What is the effect of low 2,3-DPG on the oxygen dissociation curve?

Answer 6

Causes a left shift

2,3-DPG is an important regulator of hemoglobin’s affinity for oxygen.

Question 7

What is the effect of low temperature on the oxygen dissociation curve?

Answer 7

Causes a left shift

Lower temperatures increase the affinity of hemoglobin for oxygen.

Question 8

What is the effect of raised [H+] on the oxygen dissociation curve?

Answer 8

Causes a right shift

Indicates an acidic environment.

Question 9

What is the effect of raised pCO2 on the oxygen dissociation curve?

Answer 9

Causes a right shift

Indicates higher carbon dioxide levels.

Question 10

What is the effect of raised 2,3-DPG on the oxygen dissociation curve?

Answer 10

Causes a right shift

Increases the release of oxygen from hemoglobin.

Question 11

What is the effect of raised temperature on the oxygen dissociation curve?

Answer 11

Causes a right shift

Higher temperatures decrease hemoglobin’s affinity for oxygen.