NIC Cosmetology Written (Theory) ExamScientific ConceptsEasy
A cosmetologist is explaining the structure of the hair to a client. They mention that the hair shaft is primarily composed of dead, keratinized cells. Which of the following protein is the main component of hair?
- AElastin
- BMelanin
- CCollagen
- DKeratin
Show answer & explanationAnswer & explanation
Correct answer: D. Keratin
Keratin is the primary protein that makes up hair, skin, and nails. It is a fibrous, structural protein that provides strength and protection.
Why the other options are wrong
- A. Elastin is a protein found in connective tissue that allows many tissues in the body to resume their shape after stretching or contracting, but it is not the main component of hair.
- B. Melanin is the pigment that gives hair, skin, and eyes their color, but it is not a structural protein.
- C. Collagen is a structural protein primarily found in connective tissues, skin, and bones, providing strength and elasticity, but not the main component of hair.
Keratin
A highly durable and protective fibrous protein that is the primary structural component of hair, nails, and the outermost layer of the skin (epidermis).
- Structural protein
- Main component of hair, nails, outer skin
- Provides strength and protection
- Produced by keratinocytes
Memory trick: Keratin Keeps Hair Kicking