What function hemoglobin performs?

Haemoglobin is an oxygen-binding protein found in the red blood cells of mammals and some other animals. It transports oxygen from the lungs to the rest of the body, where it is used by cells to produce energy.

The haemoglobin molecule consists of four polypeptide chains, each of which is folded into a globin domain. Each globin domain contains a haem group, which is an iron-containing porphyrin ring. The iron atom in the haem group is able to bind to oxygen molecules.

When haemoglobin is exposed to oxygen, the iron atoms in the haem groups bind to oxygen molecules, forming oxyhaemoglobin. Oxyhaemoglobin is then transported by the bloodstream to the rest of the body, where it releases the oxygen molecules into the tissues.

The release of oxygen from haemoglobin is controlled by a number of factors, including the partial pressure of oxygen in the blood, the pH of the blood, and the concentration of carbon dioxide in the blood.

Haemoglobin is an essential protein for life. Without haemoglobin, we would not be able to transport oxygen from our lungs to the rest of our body.