How do insulin work at cellular level

Insulin is produced in the pancreas' islets of Langerhans (pancreatic islets), which are small clumps of unique cells. Insulin works in tandem with glucagon, another hormone produced by the pancreas, to keep blood glucose levels in check. Insulin and glucagon are both secreted directly into the bloodstream and work together to keep blood glucose levels in check. Insulin prevents blood sugar from increasing too high, whereas glucagon prevents it from falling too low.