Haemoglobin

Question 1

What is the reason for the S-Shaped (Sigmoid) dissociation curve?

Answer 1

First Oxygen binds to Haemoglobin causing change in shape. This allows more Oxygen to bind - greater saturation with Oxygen

Question 2

What does it mean if the dissociation curve is shifted to the right?

Answer 2

Usually smaller animals with large SA/vol ratio that lose heat rapidly as respiration is faster

• Haemoglobin has lower affinity for Oxygen
• Dissociates to respiring tissues more readily at higher partial pressure of Oxygen
• Link to animal-more Oxygen to cells for more respiration to generate heat.

Question 3

What does it mean if the dissociation curve is shifted to the left?

Answer 3

Usually animals in environments with less Oxygen.

• Haemoglobin has higher affinity for Oxygen
• Haemoglobin saturated at lower partial pressure of Oxygen

Question 4

What are Haemoglobin?

Answer 4

Protein, has four polypeptides, each associated with a haem group. Each group can carry an Oxygen molecule

Question 5

Why do different animals have different Haemoglobin?

Answer 5

Have different order of amino acids- Haemoglobin have quaternary structure