Deficiency of which vitamin causes increased fragility of RBCs and muscular weakness?

Question

Accepted Answer

Vitamin E is the correct answer for the question regarding the deficiency that causes increased fragility of red blood cells (RBCs) and muscular weakness. Here's a detailed explanation:

1. **Why Option 2 (Vitamin E) is Correct:**
   - **Role of Vitamin E:** Vitamin E is a fat-soluble antioxidant that protects cell membranes from oxidative damage. It is crucial for maintaining the integrity and stability of cell membranes, including those of red blood cells and muscle cells.
   - **Deficiency Effects:** A deficiency in Vitamin E can lead to increased oxidative stress, which damages the cell membranes of RBCs, making them more fragile and prone to hemolysis (breaking down). This results in hemolytic anemia. Additionally, Vitamin E deficiency can cause muscular weakness and neurological problems due to its role in protecting nerve and muscle cells from oxidative damage.

2. **Why the Other Options are Incorrect:**
   - **Option 1 (Vitamin K):** Vitamin K is essential for blood clotting and bone metabolism. A deficiency in Vitamin K leads to bleeding disorders due to impaired clotting, not increased fragility of RBCs or muscular weakness.
   - **Option 3 (Vitamin B6):** Vitamin B6 is involved in amino acid metabolism, neurotransmitter synthesis, and hemoglobin production. Its deficiency can cause anemia, but it is typically microcytic anemia, not due to RBC fragility. It also does not directly cause muscular weakness.
   - **Option 4 (Vitamin B12):** Vitamin B12 is crucial for DNA synthesis and neurological function. A deficiency in Vitamin B12 leads to megaloblastic anemia and neurological symptoms, but it does not cause increased RBC fragility or muscular weakness in the same way Vitamin E deficiency does.

In conclusion, Vitamin E is specifically linked to the protection of cell membranes from oxidative damage, which directly relates to the symptoms of increased RBC fragility and muscular weakness. This makes Option 2 the correct answer.