| A | B |
|---|
| Trichology | study of hair |
| hair root | portion of the hair that is inside the hair follicle under skin's suface |
| hair bulb | a thickened club-shaped structure that forms lower part of the hair root |
| hair fiber | hair strand-above skin's surface |
| hair follicle | tube-like pocket root sheath |
| sebum | oil produced by sebaceous glands, it mixes with sweat to form acid mantle |
| arrector pili muscle | the muscle that makes the hair stand on end when cold or scared |
| medulla | center core of hair shaft |
| cortex | second layer-gives pigment and elasticity |
| cuticle | outside layer covering |
| texture | the degree of coarsenessor fineness in the hair fiber |
| melanin | a pigment that gives skin and hair its color |
| density | the number of active hair follicles per square inch on the scalp |
| porosity | refers to the hairs ability to absorb water and/or retain moisture |
| elasticity` | the ability of hair to stretch and return to its original shape wihtout breaking |
| keratin | protein that accounts for 90% of the makeup of hair |
| anagen | active growing stage |
| catagen | brief transitional stage |
| telogen | resting stage |
| albinism | total lack of pigment |
