Answer:
Glucagon was secreted by his pancreas before he ate the cookies because his blood glucose was low. Insulin was secreted by the pancreas after he ate the cookies because his blood glucose was high.
Explanation:
The two main cells in the islet of Langerhans are called alpha cells and beta cells. The alpha cells secrete a hormone called glucagon and the beta cells secrete insulin. Both are antagonistic hormones.
A rise in blood glucose level stimulates both the synthesis and secretion of insulin. The main functions of insulin are:
- Insulin acts mainly on hepatocytes and adipocytes
- Insulin increases the utilization of glucose in tissues and facilitates the storage of glucose and glycogen in muscles and liver by glycogenesis. By these actions, insulin lowers the blood sugar levels.
- Insulin also increases the synthesis of fat in the adipose tissue from fatty acids as well as glucose.
- it also reduces the break down and oxidation of fat.
- Promotes protein synthesis in tissues from amino acids
Glucagon acts mainly on liver cells and stimulates glycogenolysis resulting in an increased blood sugar.
Thus before having meals (cookies) the blood sugar levels may be low, due to which pancreas secrete glucagon, but after meals the blood sugar level increases thus to bring it down to normal pancreas secrete insulin.
