GLUT responsible for secretion of insulin from beta cells of pancreas –

**Core Concept**
Glucose transporter 2 (GLUT2) plays a crucial role in the regulation of glucose metabolism in the pancreas, particularly in the beta cells. It facilitates the uptake of glucose, which in turn stimulates insulin secretion.

**Why the Correct Answer is Right**
GLUT2 is responsible for the uptake of glucose in the beta cells of the pancreas. Once inside, glucose is metabolized and triggers an increase in ATP levels. This increase in ATP closes potassium channels, depolarizing the cell membrane. Depolarization opens voltage-gated calcium channels, leading to an influx of calcium ions. The increased intracellular calcium concentration stimulates the exocytosis of insulin-containing vesicles, resulting in insulin secretion.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not accurately represent the glucose transporter responsible for insulin secretion in beta cells.
**Option B:** This option is incorrect because the glucose transporter responsible for insulin secretion is not GLUT1, which is primarily found in red blood cells.
**Option C:** This option is incorrect because the glucose transporter responsible for insulin secretion is not GLUT4, which is primarily found in adipose tissue and skeletal muscle.

**Clinical Pearl / High-Yield Fact**
GLUT2 is also found in the liver and kidneys, where it plays a role in glucose sensing and regulation of glucose metabolism.

**Correct Answer:** D.