Which hair shaft component forms the outer protective covering of the strand?

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

Answer: (B)

The outer protective covering of the hair shaft is the cuticle. It’s made of flat, scale-like cells that overlap like shingles, creating a tough protective layer around the inner parts of the hair. This layer shields the cortex and any medulla from damage and helps seal in moisture, which contributes to shine and strength. The medulla is the hair’s innermost core and isn’t part of the outer surface. The cortex sits beneath the cuticle and provides most of the hair’s strength and color. The follicle is the hair’s root structure located in the skin, not a part of the strand’s surface. So, the cuticle is the correct choice because it forms the hair’s outer protective covering. When the cuticle lies smooth and intact, hair feels smooth and reflects light well; when it’s damaged or lifting, the hair looks dull and feels rough.