Which organ primarily produces erythropoietin?

The kidneys are the primary organs responsible for the production of erythropoietin. Erythropoietin is a hormone that plays a crucial role in the regulation of red blood cell production in the bone marrow. It is primarily secreted in response to low oxygen levels in the bloodstream, which is often detected through the kidneys' sensors. When oxygen levels are low, the kidneys increase erythropoietin production, stimulating the bone marrow to produce more red blood cells, thereby improving the oxygen-carrying capacity of the blood. This process is essential for maintaining adequate oxygen levels in the body and responding to various physiological needs, such as during anemia or high-altitude exposure. The other organs mentioned do not play a significant role in the production of erythropoietin.