What is the name given to component of blood that carries oxygen?

The name given to the component of blood that carries oxygen is haemoglobin. Haemoglobin is a complex protein found in red blood cells that transports oxygen from the lungs to the rest of the body. It consists of four polypeptide chains, each of which is folded into a globin domain and contains a haem group. The haem group is an iron-containing porphyrin ring that binds to oxygen molecules. When haemoglobin is saturated with oxygen, it is called oxyhaemoglobin and has a bright red colour. When it is not saturated with oxygen, it is called deoxyhaemoglobin and has a dark red colour.