Final answer:
The islets of Langerhans are responsible for regulating blood glucose levels by secreting the hormones insulin and glucagon to respectively lower and raise blood sugar.
Step-by-step explanation:
The function of the islets of Langerhans in the pancreas is to regulate blood glucose levels through the secretion of hormones. These clusters of endocrine cells uniquely manage blood sugar by releasing insulin and glucagon. Specifically, when blood glucose levels decrease, alpha cells in the islets release glucagon to increase blood sugar, primarily by signaling the liver to convert stored glycogen into glucose. Conversely, when blood glucose levels are high, beta cells emit insulin to foster the uptake of glucose by cells, thus lowering sugar levels in the bloodstream.