Malpighian tubules are found on the

Options

A. (a) distal region of mesenteron
B. (b) proximal region of mesenteron
C. (c) proximal region of proctodaeum
D. (d) junction of mesenteron & proctodaeum

Answer

**Step-by-Step Solution:**

1. **Understanding Malpighian Tubules**: Malpighian tubules are specialized excretory structures found in certain animals. They play a crucial role in the excretion of waste products.

2. **Identifying the Organism**: These tubules are primarily found in insects, which belong to the phylum Arthropoda.

3. **Location in the Digestive System**: Malpighian tubules are associated with the digestive system of insects. They are not standalone structures but are part of the elementary canal.

4. **Parts of the Elementary Canal**: The elementary canal of insects is divided into three main parts: the foregut, midgut, and hindgut.

5. **Specific Location of Malpighian Tubules**: Malpighian tubules are located at the junction of the midgut (also known as mesenteron) and the hindgut (also known as proctodeum).

6. **Evaluating the Options**:
- Option A: Distal region of mesenteron - Incorrect, as this does not correspond to the location of Malpighian tubules.
- Option B: Proximal region of mesenteron - Incorrect for the same reason.
- Option C: Proximal region of proctodeum - Incorrect, as this refers to the hindgut.
- Option D: Junction of mesenteron and proctodeum - Correct, as this is where Malpighian tubules are found.

7. **Conclusion**: Therefore, the correct answer is that Malpighian tubules are found at the junction of the midgut (mesenteron) and hindgut (proctodeum).

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