Ace the NOCTI Cosmetology Test 2025 – Style Your Success Today!

Porosity of hair specifically refers to its ability to absorb moisture. This characteristic is determined by the condition of the cuticle, which is the outer layer of the hair shaft. When the cuticle is tightly closed, hair has low porosity, indicating that it doesn't readily absorb moisture. Conversely, if the cuticle is raised or damaged, the hair has high porosity and can easily absorb moisture and other products. Understanding hair porosity is crucial for selecting the right hair care products and treatments, as different porosity levels require tailored moisture and care strategies to maintain hair health.

The other options pertain to different properties of hair. The ability to retain color is related to the hair's structure and the effectiveness of color treatments, while the ability to withstand heat involves the hair's strength and resistance to damage from styling tools. Holding styles is linked to the hair's texture and the products used to achieve the desired look.