Haemoglobin

Question 1

What is the structure of haemoglobin

Answer 1

Haemoglobin consists of 4 polypeptide chains (2 alpha and 2 beta chains).
Each chain is associated with a haem group.
Each haem group contains an iron ion (Fe²⁺) that binds to one oxygen molecule (O₂).

Question 2

What is affinity

Answer 2

The ability of haemoglobin to bind to oxygen

Question 3

What is saturation of haemoglobin with oxygen

Answer 3

Haemoglobin holding the max amount of o2 it can bind to

Question 4

What is loading/association

Answer 4

O2 binding to haemoglobin

Question 5

What is unloading/dissasociation

Answer 5

O2 unbinding from haemoglobin

Question 6

What is the cooperative nature of haemoglobin

Answer 6

Haemoglobin changes shape when the first oxygen binds, making it easier for more oxygen to bind to it

Question 7

Describe the oxyhemoglobin disassociation curve

Answer 7

02 is loaded in regions with a high partial pressure of oxygen (e.g alveoli) and o2 is unloaded in regions with a low partial pressure of oxygen (e.g respiring tissue)

Question 8

What is the Bohr effect

Answer 8

High carbon dioxide concentration causes the haemoglobin curve to shift to the right and the affinity for o2 decreases bcs the shape of the haemoglobin changes slightly due to the acidic nature of co2

Question 9

In the Bohr shift, what happens at a low partial pressure of co2

Answer 9

Low pp of co2 (e.g in alveoli) the curve shifts to the left increasing affinity so loads more o2

Question 10

In the Bohr shift, what happens at a high partial pressure of co2

Answer 10

High partial pressure (e.g at respiring tissues) the curve shifts to the right decreasing the affinity