Give other examples of disturbances in the internal environment that can act as a stimulus to a feedback mechanism.
-Erythropoeisis (production of red blood cells): The internal stimulus is hypoxia, a decrease in oxygen levels of the blood due to decreased RBCs, decreased amount of hemoglobin, or decreased availability of O2. The cells would signal hypoxia to the cells in the kidneys. Once the kidneys detect the low oxygen levels, they would release erythropoetin which is a type of protein that stimulates the red bone marrow to produce red blood cells. The enhanced erythropoesis will lead to an increase in RBC count, which could increase the oxygen levels in the blood. By the end of this process, the body is able to return to homeostasis.