Transport of oxygen

Question 1

Haemoglobin

Answer 1

• 2 alpha and 2 beta
• 1 haemoglobin bonds with 4 oxygen
• 1 oxygen with one haem

Question 2

Haemoglobin and affinity for oxygen

Answer 2

Haemoglobin can associate readily with
oxygen in places where gas exchange takes place and can dissociate at respiring tissue. Haemoglobin can do this by changing its affinity for oxygen.

Question 3

Cooperative binding

Answer 3

The firsts oxygen changes shape of haemoglobin making it easier for the second oxygen to bind.
The second oxygen changes shape making it easier for the third oxygen to bind.
Third oxygen doesn’t change the shape so it takes a large increase in partial pressure for the last oxygen to bind.