Swelling of legs and scrotum occurs due to

Options

A. blockage of lymphatic vessel by a number of worms
B. accumulation of lymph in these organs
C. accumulation of dead and living worms, lead to swelling
D. 1) and 2) are correct

Answer

**Step-by-Step Solution:**

1. **Understanding the Condition**: The swelling of legs and scrotum is a medical condition that can be caused by various factors, but in this context, we are focusing on a specific cause related to parasitic infection.

2. **Identifying the Parasite**: The primary parasite responsible for this condition is *Wuchereria bancrofti*. This is a type of nematode (roundworm) that is known to cause a disease called filariasis.

3. **Transmission of the Parasite**: The transmission of *Wuchereria bancrofti* occurs through a vector, which in this case is the mosquito. When a mosquito bites an infected individual, it can transfer the larvae of the parasite into the human bloodstream.

4. **Effect on the Lymphatic System**: Once inside the human body, the larvae migrate to the lymphatic vessels. Here, they mature and reproduce, leading to a significant increase in their population.

5. **Blockage of Lymphatic Vessels**: The large number of worms in the lymphatic vessels causes a blockage. This blockage prevents lymph fluid from properly draining, resulting in an accumulation of lymph in the affected areas.

6. **Symptoms**: The accumulation of lymph fluid leads to swelling, particularly in the legs and scrotum, which are common symptoms of filariasis.

7. **Conclusion**: Therefore, the swelling of legs and scrotum occurs due to the blockage of lymphatic vessels caused by the presence of *Wuchereria bancrofti* and the accumulation of lymph fluid.

**Final Answer**: The swelling of legs and scrotum occurs due to the blockage of lymphatic vessels by *Wuchereria bancrofti*, leading to the accumulation of lymph fluid.

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