During a political protest, a man goes on a hunger strike and confines himself to a liquid diet with minimal calories. Which of the following would occur after 4 to 5 h?
**Core Concept**
Prolonged fasting or caloric deprivation triggers a cascade of physiological responses aimed at preserving energy stores and maintaining homeostasis. The body initially breaks down glycogen stores, followed by the utilization of fat for energy production. As fasting progresses, the liver's ability to produce glucose through gluconeogenesis is impaired, leading to hypoglycemia.
**Why the Correct Answer is Right**
After 4-5 hours of fasting, the body's glycogen stores are depleted, and gluconeogenesis is not yet impaired. However, the liver's ability to produce glucose through glycolysis is still intact. As a result, the body begins to break down fat for energy production, leading to the production of ketone bodies. This process is known as ketogenesis. The correct answer reflects this physiological response to fasting.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it implies that gluconeogenesis is impaired after 4-5 hours of fasting, which is not the case.
* **Option B:** This option is incorrect because it does not accurately reflect the physiological response to fasting. After 4-5 hours, the body has not yet entered a state of ketosis.
* **Option D:** This option is incorrect because it implies that the body has entered a state of ketosis after 4-5 hours of fasting, which is not accurate.
**Clinical Pearl / High-Yield Fact**
It is essential to note that prolonged fasting can lead to a condition known as ketotic hypoglycemia, which can be life-threatening if not managed properly. This condition occurs when the body's ability to produce glucose is impaired, leading to a drop in blood glucose levels.
**Correct Answer:** C.