Main functions of the hair structure

1. 3/1/2013
Academy of Hairdressing and Beauty TAFE WSI
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Hair Structure
The Main Functions and role of the hair
•Thermo regulation – helps retains body heat
•Physical protection – acts as a buffer to knocks and abrasions
•Provides a good environment for micro organisms – increased warmth, moisture and
sebum under hair

2. Layers of the Hair
The hairshaft consists of 3 layers
1. MEDULLA
2. CORTEX
3. CUTICLE

3. MEDULLA
•Centre layer of hairshaft
•Not always present. Can be continuous or broken
•Made up of large loosely connected cells
•May contain melanin
•no known function
Source: hair

4. CORTEX
•Largest & most important layer of the hairshaft
•Determines the texture of the hair
•All chemical & physical changes take place here
•Melanin is found here – permanent colour changes
take place in the cortex
Source: hair

5. CUTICLE
•The outer layer
•Made up of clear overlapping scales
•Contains no melanin
•2 to 11 layers thick
•Protects the cortex
•Determines the hairs porosity
Source: hair

6. The Hair Follicle
The follicle is a pocket of skin and grows deep into the dermis and consists of
the following:
1. PAPILLA
2. GERMINAL MATRIX
3. HAIR BULB

7. The Papilla
•Found below the follicle in the dermis
•Is located at the base of the follicle
•Is where the CAPILLARIES pass nutrients through to dividing cells in the germinal
matrix
•Where the waste products from the cell are passed back through to the capillaries
and taken away
Source: hair follicle

8. Source: hair follicle
The Germinal Matrix
Inside the follicle above the PAPILLA
Were the cells divide ( Mitosis)
Each cell already knows if it is a cortex, cuticle or
medulla
Melanin is produced in the cells within the germinal
matrix
Cells are being pushed upwards as new cells are
produced
Once the cell leaves the germinal matrix its supply of
nutrients is cut off so he cells stop dividing and dies

9. Source: hair follicle
The Hair Bulb
•Bulb shape located at the lower end of the follicle
•The germinal matrix is found in the hair bulb
•Keratinisation occurs here

10. Sebaceous Gland
•Attached to the side of the follicle
•Secretes oil (sebum)
•Helps hair stay supple and shiny
•Sebum forms part of the acid mantle
that helps protect the skin from harmful
bacteria and chemical attackSource: hair follicle

11. Arrector Pili Muscle
•Attached to the follicle and the base of the
epidermis
•Involuntary muscle – cannot control it
•Contracts due to cold or fright creating
goose bumps
Source: hair follicle