Transport of Oxygen Flashcards
What is affinity?
A strong attraction.
What is dissociation?
It means releasing the oxygen form the oxyhaemoglobin.
What is fetal haemoglobin?
The type of haemoglobin usually found only in the fetus.
What is haemoglobin?
The red pigment used to transport oxygen in the blood
When haemoglobin associates with oxygen what does it become?
Oxyhaemoglobin
Describe the structure of haemoglobin.
Haemoglobin is a complex protein with four subunits. Each subunit consists of a polypeptide chain and a haem group. The haem group contains a single iron ion which is what associates with the oxygen.
How many molecules of oxygen can a haemoglobin group hold?
Four
How many molecules are there in each red blood cell? (estimate)
A single red blood cell can carry over a billion oxygen molecules.
Why is it difficult for the oxygen to associate with the haemoglobin in low partial pressures of oxygen?
It is difficult for the oxygen to reach the centre of the haemoglobin molecule where the haem group is. The haem group is what attracts the oxygen.
Describe the oxygen tension n the lungs and in the tissue.
The oxygen tension in the lungs is sufficiently high that it can come close to 100% oxygen saturation.
The oxygen tension in the tissues is sufficiently low that oxygen can readily disassociate from it.
Fetal haemoglobin has a higher affinity to oxygen than adult haemoglobin. Why is this beneficial?
Fetal haemoglobin must be able to associate with oxygen in an environment where the oxygen tension is low enough to make adult haemoglobin dissociate with oxygen.
