In what component of the hair is melanin located?

Melanin is the pigment responsible for the color of hair, and it is primarily located in the cortex. The cortex is the thick, middle layer of the hair shaft, which contains fibrous proteins and gives hair its strength and elasticity. Within the cortex, melanin is produced by specialized cells called melanocytes, which determine the hair's color based on the type and amount of melanin present.

The cuticle, which is the outermost layer, serves as a protective shield for the hair but does not contain melanin. The medulla, which is sometimes present as a central core in thicker hair, typically doesn't play a significant role in coloration and may not contain any melanin. The hair shaft, while encompassing all layers, itself is not the component that contains melanin but rather is the result of the structure formed by the cortex and cuticle.