Texas Esthetician License Practice Exam

What element of skin contributes to its barrier function and hydration?

1. Collagen

2. Keratin

3. Lipids

4. Melanin

The correct answer is: Lipids

The element of skin that primarily contributes to its barrier function and hydration is lipids. Lipids are essential for creating a protective barrier on the skin's surface, which helps to retain moisture and prevent transepidermal water loss. This barrier is composed of fatty acids, cholesterol, and ceramides, which work together to maintain skin hydration and integrity. A well-functioning lipid barrier is crucial for overall skin health, as it helps protect the skin from environmental aggressors, pollutants, and microorganisms, while also keeping the moisture locked in. When the lipid barrier is compromised, it can lead to dry, irritated skin and increase vulnerability to infections. Collagen, although significant for skin structure and elasticity, does not play a direct role in barrier function or hydration. Keratin contributes to the skin's structure and is vital for the formation of the outer layer of skin cells, providing strength and protection but does not directly aid in the skin's hydration. Melanin is responsible for pigmentation and offers some protection against UV radiation, but it does not affect the hydration or barrier function of the skin.