tricology
technical name for the study of hair
follicle
the tube like "pocket" that hair grows from also known as a root sheath, determines curl pattern
papilla
filled with capillaries that supply nourishment to cells around it
hair bulb
the part of the hair follicle at the base of the hair that produces new hair and grows hair
hair fiber
portion of hair that extends above the skin's surface
anagen stage
active growing stage, attached root sheath 2-6 years
catagen stage
brief transitional stage, cell division stops, a few weeks
telogen stage
resting period, no attached root sheath, hair falls out
kerantinization
process of cells changing shape, drying out and forming keratin protein
cuticle
outer layer of hair shaft, made up of overlapping transparent cells
cortex
2nd layer of hair consisting of unique structures that give the hair most of its pigment and strength (elasticity)
medulla
central core of hair shaft, not in fine hair
germinal matrix cells
undergo cell division, produce cells that ultimately keratinize and form the 3 layers of hair
arrector pilli muscle
cause hair to stand on end when a person is either cold or scared
sebaceous gland
produce sebum to prevent hair and skin form becoming too dry
sebum
oil, mixes with perspiration (sweat) to form the acid mantle
acid mantle
protects cuticle of hair fiber and maintains the natural p.H. of hair and skin
elasticity
strength of hair, ability to stretch
porosity
ability to absorb moisture
density
number of active hair follicles per square inch on the scalp
texture
degree of fineness or coarseness in the hair fiber
melanin
found in cortex
melanoctyes
produce melanosomes, which contain the pigment melanin
eumelanin
melanin that is black/brown
pheomelanin
melanin that is red/yellow
gray hair
reduced melanin in cortex, reffered to as mottled hair, grows form papilla with gray color
pityriasis capitis simplex
dry dandruff, disorder, dry flakes which can appear translucent
peduculosis capitis
disorder, infestation of head lice causing itching and eventual infection
alopecia areata
autoimmune disease, sudden loss of hair in round or irregular patches
mottled hair
gray hair
frontalis
extends from the forehead to the top of the skull, raises the eyebrows or draws the scalp forward
occipitalis
at the nape of the neck, draws the scalp back
platysma
extends from the tip of the chin to the shoulders and chest, draws the lower lip and corner of the mouth sideways and down, partially opens the mouth, as in surprise or fright
epicranius
lifts the eyebrows and the upper eyelid
temporalis
above and infront of the ear, opening and closing the jaw, as in chewing
sterno cleido mastoid
extends along the side of the neck from the ear to the collarbones, causes the head to move from side to side and up and down, nodding yes or no
nasalis
flares the nose
masseter
covers the hinge of the jaw, aids in closing the jaw, chewing
trapezius
aids in drawing the head back and elevating the shoulder blades
orbicularis oculi
circles the eye socket, closes the eyelid
orbicularis oris
circles the mouth, contracts, puckers and wrinkles the lips, as in kissing or whistling
effleurage
a light, relaxing, smoothing, gentle stroking or circular movement
petrissage
a light heavy kneading and rolling of the muscle
tapotement
a light tapping or slapping movent by the fingertips
friction
a circular or wringing movement with no gliding using the finger tips
vibration
a shaking movement in the arms