Give other examples of disturbances in the internal environment that can act as a stimulus to a feedback mechanism.
Negative mechanism - when the body develops infections from pathogens, it increases its temperature through pyrogens. The nervous system then signals the vasodilation and secretion of sweat. Both are necessary for increasing blood flow and releasing excess heat, respectively.
Positive mechanism - When the child needs more milk, the body induces lactation. The stimulus is when the baby tries to feed on the mother's mammary glands. Lactation only stops when the child decides to stop feeding.