Vörösvértestjeik

Vörösvértestjeik, also known as erythrocytes or red blood cells, are the most common type of blood cell in vertebrates. Their primary function is to transport oxygen from the lungs to the body's tissues and to carry carbon dioxide, a waste product, from the tissues back to the lungs. This vital process is facilitated by hemoglobin, a protein within red blood cells that binds to oxygen.

In mammals, mature red blood cells are enucleated, meaning they lack a nucleus, and also lack other organelles like mitochondria. This unique structure maximizes the space available for hemoglobin and allows them to be highly flexible, enabling them to squeeze through narrow capillaries. Their biconcave disc shape further enhances their surface area for gas exchange.

Red blood cells are produced in the bone marrow through a process called erythropoiesis. This process is regulated by erythropoietin, a hormone produced by the kidneys in response to low oxygen levels. The typical lifespan of a red blood cell is about 120 days, after which they are removed from circulation by macrophages in the spleen and liver.

The number of red blood cells in the blood, known as the red blood cell count, is an important indicator of health. Low red blood cell counts can lead to anemia, a condition characterized by fatigue and weakness due to insufficient oxygen delivery. Conversely, abnormally high counts can indicate conditions like polycythemia. The color of blood is predominantly due to the hemoglobin contained within these cells.