Nursing Entrance Exam Practice Test 2025 – Complete Prep Resource

When a person has fasted for an extended period, such as 24 hours without carbohydrates, the body requires a steady supply of glucose to meet its energy needs, particularly for vital organs like the brain. The liver plays a crucial role in maintaining glucose levels during fasting.

In this situation, the primary mechanism the liver employs is the conversion of glycogen into glucose. Glycogen, which is stored in the liver, acts as a readily available source of glucose. When blood glucose levels begin to drop due to fasting, the liver initiates glycogenolysis, the process of breaking down glycogen into glucose molecules. This glucose can then be released into the bloodstream, ensuring that the body has a consistent supply of energy.

This method of gluconeogenesis is vital because it enables the body to function adequately even in the absence of dietary carbohydrates. The liver's ability to efficiently manage glycogen stores is critical for maintaining homeostasis during periods of fasting.