Ch. 18 Fire Flashcards
Scientific study of hair and its diseases and care. Note: not all hair follicles contain hair.
Trichology
*Trichos is the Greek word for “hair.”
Very fine, unpigmented downy soft hair, is referred to as lanugo hair, or ______ ____. Not recommended to tweeze, shave, or wax these fine hairs. Grows on women’s cheeks… called peach fuzz.
Vellus Hair
Longer, courser hair found on the head, brows, lashes, genitals, arms, and legs. Recommended to wax.
Terminal Hair
The hair on a fetus is extremely soft and downy
Lanugo Hair
A mass of epidermal cells forming a small tube, or canal; the tube-like depression or pocket in the skin or scalp that contains the hair root. *Extends deep into the dermis.
Hair Follicle
Hair is made from a protein which is produced from the hair follicle
Keratin
It is interesting to note that as our bodies grow the follicle density we are born with does not change, but as we age it decreases because there is more surface area to cover once we grow larger and become adults.
The Hair Follicle
Anchors hair to the skin cells and is part of the hair located at the bottom of the follicle below the surface of the skin; part of the hair that lies within the follicle at its base, where the hair grows.
The Root
Is defined as the part of the hair located above the surface of the skin. (Consisting of the outer layer (cuticle), inner layer (medulla), and middle layer (cortex). Color changes happen in the cortex.)
The Shaft
The outermost layer of the hair shaft
The Cuticle
The middle of the hair shaft
The Cortex
The center or innermost layer of the hair shaft
The Medulla
The two outer layers of the shaft are hard keratin and the inner layer is soft keratin
The hair shaft
The three layers of the hair shaft
Cuticle, Cortex, and Medulla
Contains the hair follicle and its appendages: the hair root, bulb, dermal papilla, sebaceous appendage, and arrector pilii muscle.
The Pilosebaceous Unit
The main structures in the hair follicle
Root, Bulb, and Papilla
Swelling at the base of the follicle that provides the hair with nourishment; it is a thick, club-shaped structure that forms the lower part of the hair root and is made from epithelial cells that surround the papilla.
The Hair Bulb
Cone-shaped elevation at the base of the follicle, fits into the bulb. The _________ are filled with tissue that contains the blood vessels and cells necessary for hair growth and follicle nourishment.
The Hair Papilla (plural: papillae)
Attaches to the base of the hair follicle.
The Arrector Pili Muscle
Moderate amounts of ________ ___ are necessary for healthy skin and hair.
Sebaceous Oil
The four phases of the hair growth cycle
Anagen Phase, Catagen Phase, Telogen Phase, Latent Phase (ACT)
The growth stage during which new hair is produced. New keratinized cells are manufactured in the hair follicle during this phase.
Anagen Phase
The second transition stage of hair growth. In this stage, mitosis ceases. The hair grows upward and detaches itself from the dermal papilla. The mature hair is now referred to as a club hair (the base looks like a club). This is the shortest part of the growth cycle.
Catagen Phase
The final, or resting, stage of hair growth. Ready to shed.
Telogen Phase
After the telogen stage, the follicle is empty and and dormant. The old hair sheds and the cycle then begins again. The follicle can be void of hair in the telogen stage until it cycles back into the anagen stage. If the hair does not fall out and the anagen stages begins again, the two hairs can occupy the same follicle.
It takes 4 to 16 weeks for the hair to grow from the papilla to the surface of the skin, depending in part on the area of the body.
Hairs removed in the anagen stage, while the hair bulb is more “active,” will be more effective for long-term hair reduction.
Latent Phase
Generally have dark hair, with average thickness. With thicker hair, the root is quite deep in the follicle, and thus very difficult to remove.
Western Europe (France, Spain, and Portugal)
Thinner facial hair, but the roots ten to be deep.
Native American and many Asians
When is hair easier to remove
Before it turns gray
Is a good barometer of an individual’s stat of health.
Hair and Skin
Excessive hair growth on the face, arms, and legs, especially in women.
Hirsutism
Excessive growth of hair. It is characterized by the growth of terminal hair in areas of the body that normally grows only vellus hair. (full body, very extreme)
Hypertrichosis
The process of removing hair by means of electricity, is considered the only true method of permanent hair removal (verses hair reduction with lasers).
Electrolysis
This method uses *direct current, which causes chemical decomposition of the hair follicle. This method decomposes (destroys) the the papilla, the source of nourishment for the hair. The client holds the electrode connected to the positive side of the power source.
Galvanic Electrolysis
This method of electrolysis utilizes a high-frequency current to produce heat, which coagulates and destroys the hair follicle. Also known as electrocoagulation, destroys the hair by coagulating the papilla through heat. An *alternating current (AC) passes through a needle causing vibration in the water molecules surrounding the hair follicle. The action produces heat, which destroys the papilla.
Thermolysis
This method *combines both systems, sending a current through a fine needle or probe. This method combines the benefits of the galvanic and thermolysis methods by passing AC and DC current thought the needle at the same time. Quicker than galvanic method alone.
Blend