In the absence of loop of Henle

Options

A. Urine will be hypotonic
B. Urine will be hypertonic
C. Urine will be isotonic
D. No change in urine concentration

Answer

**Step-by-Step Solution:**

1. **Understanding the Nephron Structure**: The nephron is the functional unit of the kidney, consisting of the renal corpuscle (Bowman's capsule and glomerulus) and the renal tubule (PCT, loop of Henle, DCT).

2. **Role of the Loop of Henle**: The loop of Henle has two limbs: the descending limb and the ascending limb. The descending limb is permeable to water, allowing water to be reabsorbed into the bloodstream, while the ascending limb is permeable to sodium chloride (NaCl) but not to water.

3. **Concentration of Urine**: The primary function of the loop of Henle is to create a concentration gradient in the medulla of the kidney, which helps in the reabsorption of water and the production of concentrated (hypertonic) urine.

4. **Absence of the Loop of Henle**: If the loop of Henle is absent, the nephron cannot effectively concentrate urine. As a result, there will be less reabsorption of water, leading to the production of dilute urine.

5. **Conclusion**: Therefore, in the absence of the loop of Henle, the urine produced will be dilute (hypotonic) instead of concentrated (hypertonic).

**Final Answer**: In the absence of the loop of Henle, the urine will be dilute.

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