What are the three primary layers of hair?

The three primary layers of hair are indeed the cuticle, cortex, and medulla.

The cuticle is the outermost layer of the hair and consists of flattened, overlapping cells that protect the inner layers and contribute to the overall strength and shine of the hair. This layer plays a vital role in how hair appears and feels because its condition directly affects the hair's health and luster.

Beneath the cuticle lies the cortex, which is the thickest layer of the hair. The cortex is responsible for the hair's strength, texture, and color. It contains long chains of keratin, and its structure and composition determine the hair's elasticity, density, and overall appearance.

The innermost layer, the medulla, may be absent in some types of hair, but when present, it provides additional support and is thought to play a role in the hair's thermal and acoustic properties.

The other answer choices contain terms that refer to different aspects of hair and skin anatomy that are not primarily focused on the hair structure itself. Root, shaft, and tip refer to parts of the hair but do not describe the layers. The terms inner, outer, and middle are too vague and do not accurately represent the specific layers. Lastly,