Texas Esthetician License Practice Exam

Hair is primarily made up of hard keratin, a fibrous structural protein that is also a key component of other epidermal structures like nails and the outer layer of skin. Hard keratin is known for its durability and strength, providing hair with its rigidity and resistance to damage. The correct answer indicates that approximately 90% of hair consists of hard keratin, highlighting the significant role that keratin plays in hair structure and health. The remaining percentage can be attributed to water, lipids, and other substances that contribute to the overall appearance and texture of hair. In contrast, the other percentages suggest a lower composition of keratin in hair, which does not accurately reflect the dominant role that hard keratin has in contributing to the physical properties of hair. This understanding is critical for estheticians who seek to maintain and enhance hair quality through various treatments and products.