NIC Cosmetology Written (Theory) ExamScientific ConceptsEasy
What is the primary function of keratin in the hair, skin, and nails?
- ATo regulate body temperature
- BTo provide lubrication and moisture
- CTo produce pigment and color
- DTo provide strength and protection
Show answer & explanationAnswer & explanation
Correct answer: D. To provide strength and protection
Keratin is a tough, fibrous protein that forms the main structural component of hair, skin, and nails. Its primary function is to provide strength, resilience, and a protective barrier against environmental damage, pathogens, and water loss.
Why the other options are wrong
- A. Body temperature regulation involves sweat glands, blood flow, and adipose tissue, not primarily keratin.
- B. Lubrication and moisture are primarily provided by sebum (from sebaceous glands) and sweat, not keratin.
- C. Pigment and color are produced by melanin, not keratin.
Keratin
A fibrous protein that is the main structural component of hair, skin, and nails.
- Provides strength, durability, and waterproofing.
- Found in the epidermis, hair, and nails.
- Different types of keratin exist (hard and soft).
Memory trick: Keratin's 'Key' is 'Strength' and 'Shield'!