Haemoglobin

Question 1

Explain a property of iron ions that enable it to carry out its role.

Answer 1

• charged
• so associates with oxygen

Question 2

Explain how oxygen is loaded, transported and unloaded in the blood.

Answer 2

• haemoglobin has a high affinity
• in red blood cells
• loading in lungs
• at high pO2
• unloads to respiring tissues
• at low pO2
• unloads at high CO2 concentrations

Question 3

How is oxygen made available for respiration in active tissues.

Answer 3

• CO2 increases respiration
• increased dissociation of oxygen
• low partial pressure in tissues
• oxygen diffuses to tissues

Question 4

Oxygen dissociation curve of foetus is to left. Explain advantage.

Answer 4

• higher affinity
• high pO2
• oxygen diffuses from mother to foetus

Question 5

Why does the first bonding of an oxygen molecule make the second easier to bind?

Answer 5

• changes tertiary structure
• uncovers second binding site

Question 6

Describe and explain the effect of increasing carbon dioxide on the dissociation of oxyhemoglobin.

Answer 6

• increases dissociation/decreases haemoglobin affinity
• decreases pH