In the context of carbohydrate intake, what roles do insulin and glucagon play?

• A. Insulin stores energy in cells; Glucagon releases energy from cells
• B. Glucagon stores energy; Insulin releases energy
• C. Both insulins and glucagon store energy
• D. They have no role in energy balance

Answer: (A)

When carbohydrate is consumed, the body shifts into a storage mode and insulin rises. Insulin helps glucose enter cells and promotes storage of energy as glycogen in the liver and muscles, and also supports fat storage, keeping blood glucose from rising too high after a meal. When glucose is needed later (such as between meals or during exercise), glucagon rises and signals the liver to break down glycogen and to produce glucose from non-carbohydrate sources, releasing energy back into the bloodstream. So describing insulin as storing energy in cells and glucagon as releasing energy from cells matches how these hormones regulate energy balance in response to carbohydrate intake. This antagonistic pairing keeps blood glucose fairly stable: insulin lowers it after eating, while glucagon raises it during fasting or energy demand.