South Carolina Cosmetology Practice Exam

Keratin plays a vital role in the structure of hair by providing strength and elasticity. As a fibrous protein, keratin is a key structural component of hair strands, contributing to their durability and resilience. This protein forms the primary structure of hair follicles and is essential for maintaining the integrity of hair as it withstands daily wear and tear from various external factors, such as environmental exposure, heat styling, and chemical treatments. The elasticity provided by keratin allows hair to bend and flex without breaking, resulting in more manageable and less prone to damage.

Other options do not directly pertain to the core function of keratin within hair structure. While moisture and shine, color retention, and styling agents are important concerns in hair care, they are influenced by other factors and products rather than by keratin itself. Thus, understanding keratin's role is crucial for grasping how to maintain healthy hair and its appropriate care.