This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology metabolism, Subject name: Physiology
Half life of insulin is - 
Select and explain. 
A. 5min, B. 1hr, C. 12hr, D. 24hr
A: 5min
Answer: A: 5min 
Explanation: Ans. is 'a' i.e., 5 min o The half-life of insulin in the circulation in humans is about 5 min. Insulin binds to insulin receptors, and some is internalized. It is destroyed by proteases in the endosomes formed by the endocytotic process.