Haemoglobin

This presentation will examine hemoglobin with a focus on the structure and function of hemoglobin, including its role in oxygen and carbon dioxide transport. We will examine how hemoglobin's cooperative binding and physiological factors affect oxygen delivery to tissues. Key variants of hemoglobin such as those found in fetal life and genetic disorders like sickle cell disease and thalassemia will be discussed. Finally, we will consider how advances in hemoglobin research have improved diagnosis and treatment of related diseases. Let's begin by exploring the structure and vital role of hemoglobin in the body. Hemoglobin is an efficient molecule carrying oxygen from the lungs to tissues and facilitating the return of carbon dioxide. Structurally, it's a tetramer made of two alpha and two beta globin chains, each bound to a haem group containing iron essential for oxygen binding. The integrity of these chains is crucial as even minor changes can affect function and lead to disease. Hemoglobin is remarkable in how it picks up oxygen in the lungs where oxygen pressure is high and releases it in tissues where it's lower. Each ion atom in a haem group binds oxygen, saturating hemoglobin in the lungs. As blood delivers oxygen to tissues, the local drop in oxygen pressure and biochemical changes encourage hemoglobin to release oxygen. Hemoglobin also helps transport carbon dioxide both by direct binding and converting it to bicarbonate completing the cycle in the lungs.