What are the three layers of the hair shaft?

The three layers of the hair shaft are the cuticle, cortex, and medulla. Each layer has its own unique structure and function:

• The cuticle is the outermost layer, consisting of overlapping cells that protect the inner layers of the hair. Its condition can influence the overall appearance and health of the hair, as it provides a barrier against environmental damage.

• The cortex lies beneath the cuticle and makes up the majority of the hair's structure. It contains tightly packed keratin fibers and is responsible for the hair's strength, color, and texture. The cortex also holds pigment, which gives hair its color.

• The medulla is the innermost layer and may be absent in some finer hair types. In those who do have it, the medulla contains a soft, spongy substance and contributes to the hair's overall volume and flexibility.

Understanding the roles of each layer can help in identifying hair types and customizing treatments accordingly, as different hair types may require varying levels of care based on the integrity and condition of these layers. Other options provided do not correctly represent the anatomical structure of hair, as they refer to different aspects of hair growth and composition rather than the specific layers of the hair shaft.