NMAT Biology Practice Test

The hormone that raises blood glucose levels is glucagon. This peptide hormone is produced by the alpha cells of the pancreas and plays a crucial role in glucose metabolism. When blood glucose levels are low, glucagon is released into the bloodstream. Its primary function is to stimulate the liver to convert stored glycogen into glucose and subsequently release it into the blood, thus increasing blood glucose levels. In addition to glycogen breakdown, glucagon also promotes gluconeogenesis, a process where the liver produces glucose from non-carbohydrate sources, further contributing to the rise in blood glucose levels. This hormone acts in opposition to insulin, which lowers blood glucose levels by facilitating the uptake of glucose into cells and promoting its storage as glycogen. Understanding glucagon's role provides insight into how the body regulates energy balance and responds to changes in blood sugar levels, particularly during fasting or between meals when glucose is needed for energy.