A diabetic friend of yours passes out shortly after taking her insulin injection. She regains consciousness and asks you to give her one of the glucose tablets she carries in her purse. Another friend steps in and says, "Wait! You shouldn't give sugar to a diabetic!" Recalling what you learned about the endocrine system, you give your diabetic friend the glucose tablet she asked for. Why did you trust the request of your diabetic friend for the glucose tablet and not the other friend who thought he was being helpful (but wasn't)?