Insulin lowers the concentration of glucose in the blood by
- A. converting glycogen in the liver into glucose
- B. increasing the uptake of glucose by cells and its storage as glycogen in the liver and muscle
- C. increasing the excretion of glucose in the urine
- D. stopping the digestion of carbohydrate in the gut
Explanation
Insulin from the beta cells of the islets of Langerhans makes cell membranes more permeable to glucose and stimulates the enzymes that build glycogen, so glucose leaves the blood. Glucagon from the alpha cells does the opposite, breaking glycogen down when blood glucose falls, and the two hormones form a negative feedback pair. Glucose in the urine is a symptom of untreated diabetes, not the way the hormone works.