Scurvy is d ue to deficiency of –
**Core Concept**
Scurvy is a disease caused by a lack of a specific essential nutrient in the diet, which has significant implications for collagen synthesis and vascular integrity. This condition is characterized by the impairment of hydroxylation of proline and lysine residues in collagen, leading to defective collagen production and subsequent tissue damage.
**Why the Correct Answer is Right**
The correct answer is vitamin C, also known as ascorbic acid. Vitamin C plays a crucial role in the hydroxylation of proline and lysine residues in collagen, a process catalyzed by the enzyme prolyl hydroxylase. This enzyme requires vitamin C as a cofactor to facilitate the transfer of oxygen atoms to these amino acids, allowing for the formation of stable collagen triple helices. Without sufficient vitamin C, collagen production is impaired, leading to the clinical manifestations of scurvy, including poor wound healing, joint pain, and bleeding gums.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because scurvy is not caused by a deficiency of vitamin K, which is essential for blood clotting but not directly involved in collagen synthesis.
**Option B:** This option is incorrect because scurvy is not caused by a deficiency of vitamin E, which is an antioxidant involved in protecting cells from oxidative damage but not directly involved in collagen synthesis.
**Option C:** This option is incorrect because scurvy is not caused by a deficiency of vitamin D, which is essential for calcium absorption and bone mineralization but not directly involved in collagen synthesis.
**Clinical Pearl / High-Yield Fact**
One key point to remember is that scurvy can be prevented by consuming a diet rich in vitamin C-containing foods, such as citrus fruits, berries, and leafy greens. Deficiency of vitamin C can occur in individuals with poor dietary habits, malabsorption syndromes, or excessive alcohol consumption.
**Correct Answer: D. Vitamin C.**