Final answer:
Insulin lowers high blood glucose levels by promoting glucose uptake and storage, while glucagon increases low blood glucose levels by stimulating glycogen breakdown into glucose. These hormones are secreted by the pancreas, and the correct statements in the scenario are that glucagon is released before eating when glucose is low, and insulin is released after eating when glucose is high.
Step-by-step explanation:
Role of Insulin and Glucagon in Blood Glucose Regulation
Insulin and glucagon are hormones produced by the pancreas that play crucial roles in maintaining homeostasis of blood glucose levels. When blood glucose levels are high, such as after consuming food, insulin is secreted by the beta cells of the pancreas. Insulin facilitates the uptake and storage of glucose, lowering the blood glucose level. Conversely, when blood glucose levels are low, such as before a meal or during fasting, glucagon is secreted by the alpha cells of the pancreas. Glucagon promotes the breakdown of glycogen into glucose, thereby increasing the blood glucose level to normal, homeostatic levels.
The statements that accurately describe the roles of these hormones in the given scenario are:
Glucagon was secreted by his pancreas before he ate the cookies because his blood glucose was low.
Insulin was secreted after he ate the cookies because his blood glucose was high.
It is important to correct the misunderstanding that insulin or glucagon comes from the cookies themselves; these hormones are endogenous and are secreted by the pancreas in response to blood sugar levels, not directly from food.