Colorado Barbering and Cosmetology Practice Exam

What does the medulla do?

1. Provides strength to hair

2. Acts as the color pigment

3. Does nothing

4. Absorbs moisture

The correct answer is: Provides strength to hair

The medulla is the innermost layer of the hair shaft and is often described as a hollow or fibrous structure. Its exact function in hair is still a subject of research, and many experts believe that it does not significantly contribute to the properties of hair such as strength, moisture retention, or pigmentation. In many individuals, especially those with finer hair textures, the medulla may even be absent entirely. By understanding the medulla's role—or lack thereof—it becomes apparent that while other layers of the hair, such as the cortex and cuticle, are critical for strength, color, and moisture retention, the medulla itself is largely seen as nonfunctional in those respects. Therefore, calling it "does nothing" aligns with the current understanding of its minimal impact on the overall structure of the hair.