6. Erythrocytes , their physiological role. Structure of erythrocytes . Normal range of erythrocyte count.

Erythrocytes, also known as red blood cells, play a crucial role in the human body by transporting oxygen from the lungs to the tissues and removing carbon dioxide from the tissues to the lungs. They contain a protein called hemoglobin, which binds to oxygen and gives red blood cells their characteristic color.<br /><br />The structure of erythrocytes is unique and allows them to efficiently carry out their function. They are biconcave in shape, which increases their surface area and allows for faster diffusion of oxygen and carbon dioxide. Erythrocytes also lack a nucleus and other organelles, which allows for more space to carry hemoglobin.<br /><br />The normal range of erythrocyte count varies depending on the laboratory and the method used to measure it. However, a typical range is between 4.5 to 6.1 million cells per microliter of blood for adult men and 4.1 to 5.7 million cells per microliter of blood for adult women. It is important to note that these values can vary based on factors such as altitude, sex, and overall health.