What is the function of hemoglobin in red blood cells?

Hemoglobin's primary function in red blood cells is to transport oxygen from the lungs to the tissues throughout the body. This protein is specifically structured to bind with oxygen molecules; when red blood cells pass through the lungs, hemoglobin attaches to the oxygen inhaled and carries it. This binding is facilitated by the iron molecules within hemoglobin, which have a strong affinity for oxygen.

Once the red blood cells reach body tissues, hemoglobin releases the oxygen, allowing it to diffuse into cells where it is used for cellular respiration and energy production. This process highlights hemoglobin's crucial role in ensuring that all body tissues receive the necessary oxygen to function effectively.

In addition to its role in oxygen transport, hemoglobin can also bind to carbon dioxide, but its main and well-known function is the delivery of oxygen. Other options, such as aiding in blood clotting and energy production, are functions performed by different components of blood and cellular metabolism, not hemoglobin itself. These distinctions underscore the specific role of hemoglobin in maintaining the body's oxygen supply.