Glucagon is on the other side of the spectrum; it is insulin's antagonistic hormone. Glucagon is also secreted by the pancreas when glucose levels fall too low. This usually happens when a person skips meals, or does not consume adequate amounts of carbohydrates for an extended period of time. When this happens, glucagon is secreted by the pancreas to break down stored glycogen in the liver into a more usable form, glucose.
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