Hair Structure

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Hair Structure
2010-04-13 19:50:46
Hair Structure

Trichology is the scientific study of hair growth, structure and composition of hair. It is the only way to understand: Why Hair grows, Why it falls out, What creates natural color and Texture and How to spot an unhealthy scalp.
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  1. Integument
    The largest and fastest growing organ of the human body. Collectively Hair, skin and nails.
  2. What are the two parts of Hair Structure
    The Hair Root, below the scalp and The Hair Shaft, above the scalp
  3. The Hair Root
    Follicle, Hair Bulb, Dermal Papilla, Arrector Pili, & Sebaaceous Gland
  4. Follicle
    Tube like pocket in the skin that contains the root extending down from the epidermis - into the dermis where it surrounds the dermal papilla. It is not uncommon for more than one hair to grow from a single follicle.

    • Epidermis = Outer layer of skin
    • Dermis = inner layer of skin
  5. Hair Bulb
    The lowest part of the hair strand. The thick club shaped structure that forms the lower part of the hair root. The hair bulb fits over the dermal papilla.
  6. Dermal Papilla
    Covered by the hair bulb - The Dermal Papilla contains the blood & nerve supply that provides the nutrients needed for hair growth.
  7. Arrector Pili
    Think Goose Bumps... Tiny involuntary muscles in the base of the hair follicle. Strong emotions - cold causes it to contract - making hair stand straight up... Goose bumps.
  8. Subacious Gland
    The oil gland. The gland produces Sebum which lubricates the hair and skin. The oil gland is connected to the hair follicle.
  9. The Hair Shaft
    The Cuticle, Cortex and Medulla
  10. The Cuticle
    Outter most layer of the hair consists of an overlapping layer of transparent, scale-like cells. The cuticle layer protects the inner structure that lies tightly aginst the Cortex. The cuticle is responsible fot the Shine and silky smooth character of the hair. Over lapping cuticle layers is attached to the Cortex making up the cuticle layer.

    Swelling hair raises the cuticl layer and opens the space between the scales allowing liquid to penatrate into the Cortex.

    Healthy Cuticle layers prevent penatration of liquid and preserve damage. Chemical products must have a high PH/Alkaline in order to penatrate the cuticle layer. High PH swells the cuticle layer causing it to lift and expose the Cortex.
  11. The Cortex
    The middle layer - fibrous protein core formed by cells containing Melanin Pigment. Elasticity and natural color. CHEMICAL TREATMENTS TAKE PLACE HERE. 90% of weight comes from the Cortex.
  12. The Medulla
    Inner most layer of round cells. Common for very fine - naturally blonde hair to lack a medulla. Only thick course hair contains medulla. All male beards contain Medulla. Salon treatment DO NOT INVOLVE THE MEDULLA.
  13. Two types of Hair color
    Melanin and Albino

    • Melanin = grains of pigmen
    • Albino = those born without pigment in hair, skin or eyes
  14. Hair Pigment
    All natural hair color is the result of pigment located within the Cortex. There are 2 types of Melanin
  15. Two types of Melanin
    Eumelanin - Brown and black pigment and Pheomelanin - Yellow, blonde and red
  16. Color that lacks Melanin
    Gray Hair
  17. The difference between Hair Color and Haircolor
    Hair color refers to natural hair color and haircolor refers to artificial products used.