U-Shaped vessels running parallel to Henle's loop called

Answer

**Step-by-Step Solution:**

1. **Identify the Structure**: The question asks about U-shaped vessels that run parallel to Henle's loop.

2. **Understand the Nephron Anatomy**: The nephron consists of several parts, including the glomerulus, proximal convoluted tubule (PCT), loop of Henle, distal convoluted tubule (DCT), and collecting duct.

3. **Locate the Vessels**: The vessels that surround the nephron are important for the reabsorption and secretion processes. The efferent arteriole from the glomerulus gives rise to a network of capillaries.

4. **Differentiate Between Capillaries**: The capillaries surrounding the nephron are known as peritubular capillaries. However, the specific U-shaped vessels that run parallel to the loop of Henle are distinct.

5. **Identify the U-Shaped Vessels**: The U-shaped vessels that run parallel to the loop of Henle are specifically called **Vasa Recta**.

6. **Relate to Nephron Types**: Vasa Recta are more developed in juxtamedullary nephrons and are less prominent in cortical nephrons.

7. **Conclusion**: Therefore, the answer to the question is that the U-shaped vessels running parallel to Henle's loop are called **Vasa Recta**.

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