Role of Haemoglobin transporting Oxygen

Transport of oxygen

- Oxygen is transported in erythrocytes bound to the haem groups in haemoglobin

- Each molecule of haemoglobin contains four haem groups, each able to bond with one molecule of oxygen

Where does oxygen bind to?

It binds to the haem prosthetic group Fe²⁺

Oxygen + Haemoglobin ⇌

Oxyhaemoglobin

Equation

In lungs: Hb + 4O₂ → HbO₈

In tissues: Hb + 4O₂ ← HbO₈

How many molecules of oxygen can haemoglobin carry?

4 oxygen molecules, 8 oxygen atoms in total

What is the partial pressure of oxygen?

The measure of oxygen concentration

The greater the partial pressure, the higher its concentration

What is cooperative binding?

The first oxygen molecule results in a conformational change in the structure of the haemoglobin molecule

This makes it easier for each successive oxygen molecule to bind

Partial Pressure of Oxygen