What is the correct sequence of physiological events involved in maintaining blood glucose homeostasis after a person consumes a meal rich in carbohydrates?
- 1Blood glucose concentration rises above the normal set point following digestion and absorption of carbohydrates.
- 2Beta cells in the islets of Langerhans of the pancreas detect the elevated blood glucose and secrete insulin into the bloodstream.
- 3Insulin circulates through the blood and binds to specific surface membrane receptors on target liver and muscle cells.
- 4Target cells increase cellular glucose uptake and convert excess glucose into stored glycogen (glycogenesis).
- 5Blood glucose level decreases back to the normal baseline, which reduces further insulin secretion via negative feedback.
Answer
The correct sequence begins with an elevation in blood glucose levels after carbohydrate absorption, followed by the pancreatic beta cells sensing the change and secreting insulin into the bloodstream. Insulin then circulates and binds to specific cell receptors on target liver and muscle tissues, stimulating increased glucose uptake and conversion to glycogen. Finally, blood glucose concentration returns to normal baseline levels through negative feedback mechanism.
Blood glucose regulation follows a negative feedback pathway: elevated blood glucose acts as a stimulus, prompting pancreatic beta cells to release insulin into the bloodstream. Insulin binds to receptors on target tissues (liver and muscle), triggering cellular glucose absorption and storage as glycogen, which ultimately lowers blood glucose levels back to normal.
Step-by-Step Solution
Key Concept
Hormonal regulation of blood glucose concentration by insulin via negative feedback
Estimated Time:1m 30s