Both the ascending and descending limb of Henle's loop transport NaCl out to the interstitial fluid. What is the difference in their respective mode of transport?

Explanation

### Step-by-Step Solution:

1. **Understanding the Structure of the Loop of Henle**:
- The Loop of Henle consists of two main parts: the descending limb and the ascending limb. The descending limb is primarily thin, while the ascending limb has both thin and thick segments.

2. **Function of the Descending Limb**:
- The descending limb of the Loop of Henle is permeable to water but impermeable to ions such as sodium (Na+) and chloride (Cl-). This means that as the filtrate moves down the descending limb, water is reabsorbed into the interstitial fluid, concentrating the filtrate.

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