Hair

Definition

Hair is a protein filament that grows from follicles found in the dermis, or skin, consisting primarily of keratin. It serves various functions including protection, regulation of body temperature, and facilitation of evaporation of perspiration among others.

Related terms

Follicle: A small secretory cavity or sac from which hair grows, providing each strand with its own growth environment.

Keratin:

A type of protein that makes up hair, nails, and the outer layer of skin, giving them strength and resilience.

Dermis:

The thick layer of living tissue below the epidermis that forms the true skin, containing sweat glands, hair follicles, and connective tissue