Extreme porosity is defined as a condition where the cuticle is

• A. The cuticle is closed
• B. The cortex is exposed
• C. The hair is coarse
• D. The cuticle is lifted or missing

Answer: (D)

Porosity is about how easily the hair can absorb and release substances, which depends on the condition of the cuticle. Extreme porosity means the cuticle is severely damaged—lifted or missing—so the cortex is exposed. When the cuticle is compromised like this, moisture and chemicals penetrate very quickly, often leading to rapid and uneven color uptake and greater moisture loss. This contrasts with a closed cuticle, which keeps porosity low and slows absorption. Texture (hair being coarse) describes feel, not porosity, and simply saying the cortex is exposed describes the result of extreme porosity, but the defining condition is that the cuticle is lifted or missing.