The U-shaped blood vessel running parallel to the Henle's loop is `"____________"`

Explanation

**Step-by-Step Solution:**

1. **Understanding the Nephron Structure**: The nephron is the functional unit of the kidney, and it consists of various parts including the renal corpuscle, proximal tubule, loop of Henle, distal tubule, and collecting duct.

2. **Identifying the U-shaped Blood Vessel**: Within the nephron, there is a specific blood vessel that runs parallel to the loop of Henle. This blood vessel is crucial for the kidney's function.

3. **Recognizing the Name of the Blood Vessel**: The U-shaped blood vessel that runs parallel to the loop of Henle is known as the "limb of the vasa recta".

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