Properties Of The Hair And Scalp Flashcards
Alopecia
Abnormal hair loss. (3 common types: androgenic, areata, and postpartum)
Alopecia areata
An autoimmune disorder that causes the effected hair follicles to be mistakenly attacked by a persons own immune system.
Alopecia totalis
Hair disorder that begins with one or more small, round or smooth bald patches on the scalp and can progress to total scalp hair loss.
Alopecia universalis
Complete body hair loss.
Trichology
The scientific study of hair and its diseases.
Hair root
The part of the hair located below the surface of the epidermis (outer layer of the skin).
Hair shaft
Portion of the hair that projects above the epidermis.
Hair follicle
Is the tube-like depression or pocket in the skin or scalp the contains the hair root. The follicle extends downward from the epidermis into the dermis (the inner layer of skin) where it surrounds the dermal papilla.
Hair bulb
The lowest part of a hair strand. It is the thickened, club-shaped structure that forms the lower part of the hair root.
Dermal papilla
Small cone shaped elevation located at the base of the hair follicle that fits into the hair bulb. (“Mother of the hair” because it contains the blood and nerve supply the provides nutrients for hair growth).
Arrector pili
small, involuntary muscle in the base of the hair follicle. (goose bumps are caused by the contracting of this muscle).
Sebaceous glands
Oil glands in the skin that are connected to the hair follicles. These glands secrete fatty or an oily substance called sebum. Sebum lubricates the skin.
3 main layers of the hair shaft
Hair cuticle, Cortez and medulla.
Hair cuticle
The outermost layer of the hair.it consists of transparent, scale-like cells that look like shingles on a roof. It protects the inner structure of the hair.
Cortex
Middle layer of the hair. It is a fibrous protein core formed by elongated cells containing melanin pigment.
Medulla
The innermost layer of the hair and is composed of round cells.
Keratinization
The process in which hair follicles mature. As the newly cells mature, they fill up with a fibrous protein called keratin.
COHNS elements
Major elements that make up the human hair. Carbon, oxygen, hydrogen, nitrogen, and sulfur.