Hair structure

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...

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?

The primary function of hair is what?

The eyes are protected by what hairs?

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?

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

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

causes dry hair and scalp

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......

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....

What can repeat opening and closing of the cuticle do?

dirt and hairspray get caught in what layer of hair?

elongated cells

middle layer of the hair
largest layer
makes up 75%-90% of hairs composition

Where all the chemical action takes place?

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.
stronger
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
more fragile
easier to process

Measures the

measures the number of individual hairs per square inch

On average people with blonde hair have how many hair on their head?

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?

The ability of the hair to absorb liquids
☆Related to the condition of the cuticle layer

Cuticle type
Not very porous
Resists liquids
Water may roll off the hair when first sprayed
Requires stronger solutions (alkalines)

Cuticle type that
More porous
absorbs liquids easier
hair drys slower
chemically treated
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 what kind of elasticity will break easily, will tangle easily, and will not hold a curl when set?

What test do you perform for elasticity?

When is analyzing the growth pattern of hair most important?

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
 pigmented

Hair on the head can be referred as....

eyelashes

eyebrows

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?

90% of hair is in this phase

Phase that is..
transition period
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