NIC Barber Written (Theory) ExamScientific ConceptsEasy
A barber is performing a chemical service that requires the product to penetrate the hair's cuticle and modify its internal structure. Which layer of the hair is the primary target for such chemical changes?
- AMedulla
- BFollicle
- CCortex
- DCuticle
Show answer & explanationAnswer & explanation
Correct answer: C. Cortex
The cortex is the middle layer of the hair, composed of keratin proteins, and is responsible for the hair's strength, elasticity, and color. Chemical services target the cortex to make lasting changes.
Why the other options are wrong
- A. The medulla is the innermost, sometimes absent, layer and is not primarily involved in chemical services.
- B. The follicle is the structure from which hair grows, not a layer of the hair shaft itself.
- D. The cuticle is the outermost protective layer; chemicals must pass through it to reach the cortex.
Hair Cortex
The middle layer of the hair shaft, composed of fibrous protein and melanin pigments, responsible for the hair's strength, elasticity, and natural color.
- Contains melanin (color pigment).
- Accounts for most of hair's weight and strength.
- Target for chemical services (perms, relaxers, color).
Memory trick: Cuticle is the Coat, Cortex is the Core, Medulla is the Middle.