Proximal and distal convoluted tubules are parts of

Options

A. Seminiferrous tubules
B. Nephron
C. Oviduct
D. Vas deferens

Answer

### Step-by-Step Solution:

1. **Identify the Terms**: The question mentions "proximal convoluted tubules" and "distal convoluted tubules." These are specific structures within the kidney.

2. **Define the Structures**:
- The **proximal convoluted tubule (PCT)** is the first segment of the renal tubule, responsible for reabsorbing water, ions, and nutrients from the filtrate.
- The **distal convoluted tubule (DCT)** is the segment that follows the loop of Henle and is involved in the reabsorption of sodium and chloride ions and the secretion of potassium and hydrogen ions.

3. **Locate the Structures**: Both the PCT and DCT are located within the nephron, which is the functional unit of the kidney.

4. **Understand the Nephron**: The nephron consists of several parts:
- **Bowman's capsule**: where filtration occurs.
- **Glomerulus**: a network of capillaries within the Bowman's capsule.
- **Proximal convoluted tubule (PCT)**: follows the Bowman's capsule.
- **Loop of Henle**: follows the PCT.
- **Distal convoluted tubule (DCT)**: follows the loop of Henle.
- **Collecting duct**: final part of the nephron.

5. **Conclusion**: Since both the proximal and distal convoluted tubules are parts of the nephron, the answer to the question is that they are parts of the nephron.

### Final Answer:
Proximal and distal convoluted tubules are parts of the **nephron**.

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