Insulin's secretion and metabolism basics Steps:

• Recall insulin is a hormone secreted by pancreatic beta cells to lower blood glucose.
• Evaluate A: Insulin promotes glycogenesis (glucose to glycogen), not the reverse.
• Evaluate B: Insulin degradation occurs mainly in kidneys (30-40% of circulating levels) and peripheral tissues via insulin-degrading enzyme; liver handles first-pass but not primary breakdown of systemic insulin.
• Evaluate C: Secretion is from pancreas, not liver.
• Evaluate D: Insulin release decreases blood glucose by promoting uptake and storage.

Why B is correct:

• Insulin is primarily degraded by kidneys and tissues, not the liver as the main site (per metabolic clearance studies).

Why the others are wrong:

• A: Insulin facilitates glucose conversion to glycogen, inhibiting glycogen to glucose breakdown.
• C: Insulin is secreted exclusively by pancreatic beta cells.
• D: Insulin release lowers blood glucose levels.

Final answer: B