Arrange the following in sequence occurring in fed state 1. Insulin 2. GLUT-2 3. Uptake of glucose by skeletal muscles 4. GLUT-4
**Core Concept**
The fed state is characterized by increased glucose levels in the blood, triggering an insulin-mediated response to facilitate glucose uptake by cells. **Insulin** plays a crucial role in this process by stimulating the translocation of specific glucose transporters. The primary glucose transporters involved in this process are **GLUT-2** and **GLUT-4**.
**Why the Correct Answer is Right**
In the fed state, the ingestion of food leads to an increase in blood glucose levels, prompting the release of **insulin** from the pancreas. **Insulin** then stimulates the translocation of **GLUT-4** to the surface of skeletal muscle cells, enhancing the uptake of glucose by these cells. **GLUT-2**, on the other hand, is primarily involved in the transport of glucose across the intestinal and renal epithelial cells.
**Why Each Wrong Option is Incorrect**
**Option A:** This sequence is incorrect because **GLUT-2** is not directly involved in the uptake of glucose by skeletal muscles in response to insulin.
**Option B:** This option is incorrect as it places **uptake of glucose by skeletal muscles** before the action of **insulin**, which is not the correct sequence.
**Option D:** This option incorrectly places **GLUT-4** before **insulin**, which does not accurately reflect the insulin-mediated translocation of **GLUT-4**.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that **insulin** stimulates the translocation of **GLUT-4** to the surface of skeletal muscle cells, thereby facilitating the uptake of glucose and reducing blood glucose levels.
**Correct Answer: 1. Insulin, 2. GLUT-4, 3. Uptake of glucose by skeletal muscles, 4. GLUT-2**