Question 37

Keratin is the type of protein found in nails.

Nails are primarily composed of keratin, a tough and fibrous protein that provides structure and strength. This protein is essential for the protective function of nails.

A) collagen

Collagen is a structural protein found in connective tissues such as skin, tendons, and ligaments, but it is not the primary protein in nails. While collagen contributes to the overall health of skin and may be present in the nail bed, it does not constitute the main component of nails.

B) disulfide

Disulfide refers to a type of bond (specifically, disulfide bridges) that can form between amino acids in proteins, contributing to the stability and structure of proteins like keratin. However, it is not a type of protein itself and therefore does not answer the question regarding the specific type of protein found in nails.

C) fibrous

While keratin is indeed a fibrous protein, simply stating "fibrous" does not specify the type of protein present in nails. The term is too broad and includes various proteins, whereas the specific protein in nails is keratin.

D) keratin

Keratin is the correct answer as it is a fibrous structural protein that forms the main component of nails, hair, and the outer layer of skin. It provides the necessary strength and resilience that nails require.

Conclusion

Keratin is definitively identified as the primary protein in nails, serving crucial structural roles. Other options, while related to protein structures or types, do not specifically pertain to the composition of nails, making them incorrect in this context. Thus, option D stands out as the accurate choice.