The thin segment of descending limb of Loop of Henle is lined by

Options

A. Columnar cells
B. Flat cells
C. Cuboidal cells
D. Pyramidal cells with characteristic brush border

Answer

To answer the question "The thin segment of the descending limb of the Loop of Henle is lined by," we can follow these steps:

### Step 1: Understand the Structure of the Nephron
The nephron is the functional and structural unit of the kidney. It consists of several parts, including the glomerulus, Bowman’s capsule, proximal convoluted tubule (PCT), Loop of Henle, distal convoluted tubule (DCT), and collecting duct.

**Hint:** Familiarize yourself with the parts of the nephron and their functions.

### Step 2: Identify the Loop of Henle
The Loop of Henle is a U-shaped structure that consists of two limbs: the descending limb and the ascending limb. The descending limb is responsible for the reabsorption of water.

**Hint:** Remember that the Loop of Henle plays a crucial role in urine concentration.

### Step 3: Analyze the Characteristics of the Descending Limb
The descending limb of the Loop of Henle is characterized by being permeable to water but impermeable to electrolytes. This means that as the filtrate moves down this limb, water is reabsorbed, concentrating the solutes in the filtrate.

**Hint:** Consider the permeability characteristics of the descending limb when thinking about its lining.

### Step 4: Determine the Type of Cells Lining the Descending Limb
The thin segment of the descending limb is lined by simple squamous epithelium, which consists of flat cells. This structure is ideal for facilitating the movement of water.

**Hint:** Think about the shape of the cells and their role in the function of the descending limb.

### Step 5: Choose the Correct Answer
Based on the analysis, the correct answer to the question is that the thin segment of the descending limb of the Loop of Henle is lined by "flat cells" (simple squamous epithelium).

**Hint:** Review the options provided and select the one that corresponds to the characteristics of the cells lining the descending limb.

### Final Answer
The thin segment of the descending limb of the Loop of Henle is lined by flat cells (simple squamous epithelium).

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