試題詳解

21. Which of the following statements correctly describes the roles of insulin and glucagon in glucose homeostasis?
(A) Insulin promotes glycogenolysis and gluconeogenesis in the liver, while glucagon promotes glycolysis and glycogenesis.
(B) Insulin stimulates glucose uptake in muscle and adipose tissues by upregulating GLUT4 transporters, whereas glucagon primarily acts on the liver to increase glucose production.
(C) Insulin inhibits lipogenesis and enhances β-oxidation of fatty acids, whereas glucagon stimulates lipogenesis and inhibits β-oxidation.
(D) Both insulin and glucagon act through receptor tyrosine kinases to mediate their effects on target tissues.
(E) Insulin and glucagon are secreted by pancreatic β-cells in response to high glucose levels.