It was observed that blood glucose levels were falling in an individual. this event would be sensed by (a) cells in the (b) of the pancreas, causing them to release the hormone (c). this series of events would be part of an (d) loop/mechanism, serving as a self-adjusting mechanism for maintaining normal levels of blood glucose.
i thought it was alpha cells in the islet of the pancreas releasing glucagon, but what is the loop?