( A ) The glucose homeostasis in blood is maintained jointly by insulin and glucagon.
( B ) Insulin is a peptide hormone, which plays a major role in the regulation of glucose homeostasis.
( C ) Glucagon is a glycopeptide hormone, and plays an important role in maintaining the normal blood glucose levels.
( D ) The α-cells secrete a hormone called glucagon, while the β-cells secrete insulin.
