The homeostasis of blood sugar levels in controlled via a careful balance of hormonal secretions leading to an increase of blood sugar concentation when needed. when the blood sugar concentration is too high the beta-cells in the islets of langerhans are able to detect and begin to secret insulin. When insulin is secreted into the blood stream it is recieved by the receptors that are present on cells in the body, these cells whose insulin receptors have binded to insulin then absorb glucsoe as a result, which leads to a decrese in the blood sugar concentration. When the blood sugar is too low cells in the body begin to secret glucagon. When a glucagon binds to the recpetors on cells these cells will release glucose into the blood, this glucose can either be stored in the cell or the cell may undergo gluconeogenesis, which is the formation of glucose from other organic moleculs such as proteins as lipids, these are all then released into the blood stream to help revert the blood glucose concentration to a healthier level. This is an example of a negative feedback mechanism.