Which physiological adaptation occurs in the lungs due to chronic hypoxia?

In response to chronic hypoxia, the body undergoes several physiological adaptations to improve oxygen delivery to tissues, one of which is increased production of red blood cells, a process known as erythropoiesis. When oxygen levels are consistently low, the kidneys detect this deficiency and release more erythropoietin (EPO), a hormone that stimulates the bone marrow to produce more red blood cells. This increase in red blood cell count enhances the oxygen-carrying capacity of the blood, helping to compensate for the inadequate oxygen availability in the environment.

This adaptation is particularly vital in conditions such as living at high altitudes or in chronic lung diseases, where oxygen levels may be persistently low. Through this compensatory mechanism, the body attempts to maintain adequate oxygen delivery to vital organs and tissues, which can help mitigate some of the adverse effects of chronic hypoxia.

Other physiological responses to chronic hypoxia can involve changes in lung structure and function as well, but in the context of the question, the significant increase in red blood cell production is a hallmark adaptation.