Question 15

The skin aids in maintaining calcium and phosphate levels through Vitamin D production.

The skin plays a crucial role in regulating calcium and phosphate levels in the body primarily by producing Vitamin D. This vitamin is essential for calcium absorption in the intestines and helps maintain adequate serum calcium and phosphate concentrations.

A) Sebum production

Sebum production refers to the secretion of oils by sebaceous glands, which helps in moisturizing and protecting the skin. While important for skin health, it does not have a direct role in the regulation of calcium and phosphate levels in the body.

B) Keratin synthesis

Keratin synthesis involves the production of keratin, a structural protein that provides strength and resilience to the skin, hair, and nails. Although keratin is vital for the integrity of skin tissues, it does not influence the body's calcium and phosphate balance.

C) Vitamin A synthesis

Vitamin A synthesis is related to the skin's ability to convert certain compounds into Vitamin A, which is important for vision, immune function, and skin health. However, this process does not impact the regulation of calcium and phosphate levels in the body.

D) Vitamin D production

Vitamin D production is a critical function of the skin, which synthesizes this vitamin in response to sunlight exposure. Vitamin D is essential for calcium absorption from the diet and plays a significant role in maintaining optimal levels of calcium and phosphate in the bloodstream.

Conclusion

Vitamin D production is the key mechanism by which the skin aids in maintaining calcium and phosphate levels in the body. Unlike the other options, which focus on different aspects of skin function, Vitamin D directly influences the absorption of calcium, making it indispensable for skeletal health and metabolic balance. Thus, D is the definitive correct answer.