Which protein serves as a chemical messenger?
I would also agree that the answer is insulin
insulin is known as an endocrine hormone. The endocrine glands are what produce hormones. Insulin is a protein that is made by the beta cells , which are found in the pancreas. Beta cells major function is to store and then release insulin.
Hopefully this helped and good luck. If you need me to clarify anything just let me know.
Answer would be insulin
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