Fibrous protein layer of hair responsible for strength, elasticity, and color.

Fibrous protein layer of hair responsible for strength, elasticity, and color.

• A. Cortex
• B. Cuticle
• C. Medulla
• D. Follicle

Answer: (A)

The cortex is the fibrous protein layer that gives hair its strength, elasticity, and color. It sits beneath the outer cuticle and is filled with keratin fibers arranged in a way that provides mechanical resilience, so hair doesn’t break easily and can stretch a bit without snapping. Melanin pigments inside cortex cells determine hair color, which is why color is associated with this layer. The outer cuticle is the protective cover of flattened cells that shields the cortex, not the main source of strength or color. The medulla, when present, is the soft central core and contributes less to strength and color. The follicle is the hair’s root inside the skin, supplying nutrients and growth, not a part of the hair shaft’s strength or pigment.

The cortex is the fibrous protein layer that gives hair its strength, elasticity, and color. It sits beneath the outer cuticle and is filled with keratin fibers arranged in a way that provides mechanical resilience, so hair doesn’t break easily and can stretch a bit without snapping. Melanin pigments inside cortex cells determine hair color, which is why color is associated with this layer. The outer cuticle is the protective cover of flattened cells that shields the cortex, not the main source of strength or color. The medulla, when present, is the soft central core and contributes less to strength and color. The follicle is the hair’s root inside the skin, supplying nutrients and growth, not a part of the hair shaft’s strength or pigment.