Lighteners utilize ingredients such as ammonia and peroxide to penetrate the cortex and:

Lighteners utilize ingredients such as ammonia and peroxide to penetrate the cortex and:

• A. Cause Melanin to Break Down
• B. Slow the Decolorization
• C. Seal the Cuticle
• D. Remove Pigment Only from the Surface

Answer: (A)

Lighteners work by opening the hair cuticle and delivering an oxidizing agent into the cortex, where they oxidize melanin—the natural pigment in hair. Ammonia raises the pH to lift the cuticle, and peroxide provides the oxygen that oxidizes pigment molecules. As melanin is oxidized, its large pigment molecules break down into smaller, colorless fragments, which causes the hair to lighten. So the best description is that lighteners cause melanin to break down. The other ideas don’t fit because pigment isn’t simply removed from the surface, the cuticle isn’t sealed by lighteners, and decolorization isn’t slowed—it’s driven by oxidation inside the cortex.

Lighteners work by opening the hair cuticle and delivering an oxidizing agent into the cortex, where they oxidize melanin—the natural pigment in hair. Ammonia raises the pH to lift the cuticle, and peroxide provides the oxygen that oxidizes pigment molecules. As melanin is oxidized, its large pigment molecules break down into smaller, colorless fragments, which causes the hair to lighten. So the best description is that lighteners cause melanin to break down. The other ideas don’t fit because pigment isn’t simply removed from the surface, the cuticle isn’t sealed by lighteners, and decolorization isn’t slowed—it’s driven by oxidation inside the cortex.