Card Set Information
The scientific study of hair and it's diseases is?
A slender, thread like appendage of the skin is?
Hair is made up of hard protein called?
Hair has no sense of feeling because...
there are no nerve fibers in the hair shaft
Hair has a pH of ....
Unlike skin, hair has no power of...
The average person loses how many hairs a day?
Hair is found all over the body expect for what two places?
palms of hands and soles of feet
The primary function of hair is what?
protection and adornment
The eyes are protected by what hairs?
the eyelashes and eyebrows
Hair grows and average of how many inches a month?
Ethnic hair grows
Age, overall health,diet, stress, medications, illness, and hormones are all factors that affect what?
The hair root is the portion of the hair located below the what?
the surface of the scalp
Tube-like depression or pocket in the skin that contains the hair root
the number of hair follicles for an adult human is estimated to be what?
Is related to the shape and size of the follicle
thick, club like structure that forms the lower part of the hair root
Wraps around the hair bulb allowing you to feel when someone touches your hair
sensory never fibers
the hair bulb fits over the____ and receives nutrients
small cone shaped elevation located at the base of the hair follicle
fits into the hair bulb and contains the blood and provides nutrients needed for growth and growth
Aids in the process of keratinization
"living part of the hair"
"mother of the hair"
involuntary muscle fiber in the skin inserted at the base of the hair follicle
responds to fear and cold
muscle contracts, makes the hair stand up straight, resulting in "goose bumps"
oil glands of the skin connected to the hair follicles
produces an oily substance called sebum which lubricates the hair and the skin
provides luster and pliability to the hair
causes oily hair and scalp
overactive sebaceous glands
causes dry hair and scalp
under active sebaceous glands
Amount of _____ produced depends on; metabolism, emotions, endocrine glands, blood circulation, and diet
the portion of the hair that projects above the skin
scale like cells
outer most layer of the hair
accounts for 10% to 25% of the composition of the hair
overlapping transparent scale-like cells
cuticle scales point.....
A healthy cuticle is the hair's......
defense against damage
protects the cortex
This ethnicity has the least amount of cuticle scales
This ethnicity has an intermediate amount of cuticle scales
This ethnicity has the largest amount of cuticle scales
A tough, compact cuticle results in....
weak, loosened cuticle results in.....
solutions must have a pH above what in order to open the cuticle?
swelling of the cuticle layer makes the hair feel....
dry and rough
What can repeat opening and closing of the cuticle do?
damage the cuticle leaving the hair more porous
dirt and hairspray get caught in what layer of hair?
middle layer of the hair
makes up 75%-90% of hairs composition
Where all the chemical action takes place?
In the cortex
Contributes to the physical and chemical properties of the hair
The bonds that allow the hair to be changed chemically
Elasticity, texture, strength, and color are all what?
Grains of pigment that give the natural color to the hair
Provides black and brown color (blue pigments)
Provides the warmer tones of the hair (red and yellow pigments)
What is the result of a ratio of eumelanin and pheomelanin and the size of the melanin molecules?
Dark hair has more what than lighter hair?
When there is an absence of pigment, air space develop, resulting in what?
A person born with no melanin in the hair, skin, or eyes is called? ( usually born with white hair)
This layer of the hair has no purpose. Round cells
Is the innermost layer of the hair
Common for very fine hair and blonde hair to lack this layer of the hair. Coarse hair usually has this layer.
Known as an air space cavity
layer that is very fragile and can be destroyed by chemical services
how the hair feels
diameter (thickness) of the individual strand
what are three different types of texture?
The texture type that has the largest diameter.
usually requires longer processing time or stronger chemicals
The texture type that is considered normal
Stand to which all other hair is compared
texture type that has the smallest diameter
easier to process
measures the number of individual hairs per square inch
On average people with blonde hair have how many hair on their head?
140,000 (highest density)
On average people with brown hair have how many hairs on their head?
On average people with black hair have how many hairs on their head?
On average people with red hair have how many hairs on their head?
80,000 (lowest density)
The ability of the hair to absorb liquids
☆Related to the condition of the cuticle layer
Not very porous
Water may roll off the hair when first sprayed
Requires stronger solutions (alkalines)
Cuticle type that
absorbs liquids easier
hair drys slower
requires mild chemicals (acids)
What can help achieve even porosity results when preforming chemical services?
How do you test for porosity
The ability of the hair to stretch and return to it's original size without breaking
wet hair should stretch up to what % without breaking?
Dry hair should stretch up to what % without breaking?
Hair with what kind of elasticity will not break, doesn't tangle easy, and will hold a curl when set?
Hair with good elasticity
Hair with what kind of elasticity will break easily, will tangle easily, and will not hold a curl when set?
Hair with poor elasticity
What test do you perform for elasticity?
When is analyzing the growth pattern of hair most important?
When hair cutting and determining hairstyles for you client
Hair growing in the same direction. directly related to the hair follicles
Hair that forms a circular pattern. Very common in the crown and nape area.
Tuft of hair that stands straight. Usually most noticeable in the front hairline
short, fine hair that covers the body
not usually pigmented
long,soft hair found on the scalp, legs and arms
Hair on the head can be referred as....
The three life cycles of hair
the growth phase of hair
keratinization is active during this phase
What is the average life cycle of hair?
Once the hair reaches approximately ____ inches in length, the rate of hair growth will slow down.
Hair on what part of the body has the longest life cycle?
the hair on the scalp
90% of hair is in this phase
Phase that is..
the end of the growth phase
in this phase..
follicle shrinks and the air bulb detaches from the papilla
hair bulb shrinks, forming a round club
last approximately 1-2 weeks
1% of the hair is in this phase
this phase is...
the resting phase
hair is shed or hair remains in place until the next anagen phase
this phase lasts approximately 3-6 months and is 10% of the hair is in this phase