North Dakota Cosmetology Practice Exam

Which of the following lists the three layers of the hair strand?

1. Medulla, cortex, bulb

2. Cuticle, cortex, medulla

3. Cuticle, shaft, root

4. Cortex, bulb, root

The correct answer is: Cuticle, cortex, medulla

The three layers of the hair strand are the cuticle, cortex, and medulla. The cuticle is the outermost layer, consisting of transparent, scale-like cells that protect the inner structures of the hair. It plays a critical role in the hair’s overall health and appearance, as it can affect shine and strength. The cortex lies beneath the cuticle and is the thickest layer of the hair strand. It contains fibrous proteins and is responsible for the hair's strength, color, and texture. The cortex's structure is vital for determining how well hair can hold styles and how it reacts to various treatments. The medulla is the innermost layer and may not be present in all hair types. It has a soft, spongy composition, and while its function is not fully understood, it is believed to contribute to the overall integrity of the hair strand. This answer accurately reflects the three key layers that constitute the structure of hair, highlighting their individual roles and characteristics. The other options listed do not accurately represent the layers of the hair, which is why the choice identifying the cuticle, cortex, and medulla is correct.