Properties of the Hair & Scalp

structure

All professional hair services must be based on a thorough understanding of the growth, ________, & composition of hair.

trichology; trichos; ology

__________ is the scientific study of hair & its diseases & care which comes from the Greek words _____, meaning “hair”, & ______, meaning “the study of”.

hair root; hair shaft

A mature strand of human hair is divided into 2 parts: the _______, located below the surface of the epidermis, & the _________, the portion of the hair that projects above the epidermis.

hair follicle

the tube-like depression or pocket in the skin or scalp that contains the hair root

hair bulb

the thickened, club-shaped structure that forms the lower part of the root

dermal papilla

small, cone-shaped elevation located at the base of the hair follicle that fits into the hair bulb

arrector pili muscle

small, involuntary muscle in the base of the hair follicle

sebaceous glands

the oil glands in the skin that are connected to the hair follicles

palms; soles

Hair follicles are distributed all over the body, with the exception of ______ & ______.

False

True or False: More than one hair will never grow from a single follicle.

bulb

The lowest part of the hair strand is called the hair _____.

dermal papillae

Which part of the hair root contains the blood & nerve supply that provides the nutrients needed for hair growth?

arrector pili muscle

Which muscle causes goose bumps when it contracts due to strong emotions or a cold sensation?

sebum

The sebaceous glands secrete a fatty or an oily substance called _____, which lubricates the skin.

hair cuticle, cortex, medulla

What are the 3 main layers of the hair shaft?

cuticle

The outermost layer of the hair is the ______.

high pH swells the cuticle & causes lift exposing the cortex

Why must oxidation haircolors, permanent waving solutions, & chemical hair relaxers have an alkaline pH?

middle layer

Which layer of the hair is the cortex?

90 percent

What percentage of the total weight of the hair comes from the cortex?

weight, elasticity, color

Name 3 different hair properties for which the cortex is responsible.

cortex

In what layer of the hair do changes involving oxidation haircoloring, wet setting, thermal styling, permanent waving, & chemical hair relaxing take place?

medulla

The ________ is the innermost layer of the hair & is composed of round cells.

False

True or False: All hair has 3 layers of the hair shaft.

True

True or False: All male beard hair contains a medulla.

False

True or False: The medulla is involved in salon services.

protein

Hair is composed of ________ that grows from cells originating within the hair follicle.

keratinization

The maturation of cells within the hair follicle is called __________.

carbon-51%

oxygen-21%

hydrogen-6%

nitrogen-17%

sulfur-5%

List the 5 main elements that make up human hair & their percentage in normal hair.

COHNS; skin; nails

Together, the 5 elements that make up human hair are referred to as the _______ elements to help people remember them; they are also found in the _____ & the _____.

amino acids

units that are joined together & make up proteins

helix

the spiral shape of a coiled protein

peptide bond

the strong, chemical bond that joins amino acids

polypeptide chain

a long chain of amino acids linked by peptide bonds

hydrogen, salt, disulfide

Polypeptide chains are cross-linked like the rungs on a ladder by 3 different types of side bonds called what?

hydrogen; dries

A _________ bond is a weak, physical, cross-link side bond that is easily broken by water or heat; these bonds reform when the hair ______.

salt

Weak, physical, cross-linked side bonds between adjacent polypeptide chains are ______ bonds.

disulfide

A ________ bond is a strong, chemical side bond that joins the sulfur atoms of two neighboring cysteine amino acids to create one cystine.

melanin

_________ are the tiny grains of pigment in the cortex that give natural color to the hair.

eumelanin- dark brown to black

pheomelanin- red & ginger to yellow & blonde

List and describe the 2 types of melanin in relation to hair

wave pattern; straight; wavy; curly; extremely curly

The ________ of hair refers to the shape of the hair strand & is described as ________, ________, _______, or ___________.

genetics

Natural wave patterns are a result of _________.

straight; extremely curly

Asians & Native Americans tend to have _______ hair, while African Americans tend to have ____________ hair; however, anyone of any race, or mixed race, can have hair with varying degrees of curl.

flattened

In extremely curly hair, cross-sections appear ___________ & vary in shape & thickness along their length.

True

True or False: The shape of a cross-section of hair always relates to the amount of curl in the hair.

low

Extremely curly hair often has _____ elasticity.

vellus; terminal

The 2 main types of hair found on the body are ______ hair and ________ hair.

55%

Men retain _____ less vellus hair than women.

True

True or False: All hair follicles are capable of producing either vellus or terminal hair, depending on genetics, age, & hormones.

anagen

The growth phase of new hair is ________.

catagen

The transition period between the growth & resting phases is called _________.

telogen

The resting phase of hair is ________.

½ inch

What is the average growth of healthy scalp hair per month?

15 & 30

Between what ages does scalp hair tend to grow most rapidly?

less than 1 percent

What percentage of scalp hair is in the catagen phase at any one time?

A little less than 10 percent

What percentage of scalp hair is in the telogen phase at any one time?

3-5 years

How long does the anagen phase generally last?

False

True or False: Shaving, clipping, & cutting the hair makes it grow back faster, darker, & coarser.

True

True or False: Under normal circumstances, everyone loses some hair every day.

35-40 hairs

According to recent measurements, the average rate of hair loss is _______ hairs per day.

alopecia

Abnormal hair loss is called ________.

androgenic alopecia; miniturize

________________ is the result of genetics, age, or hormonal changes that cause terminal hair to _________.

male pattern baldness

In men, androgenic alopecia is known as _______________ & usually progresses to the familiar horseshoe-shaped fringe of hair.

hair loss

By the age of 35, 40% of men & women show some degree of _________.

autoimmune disorder that causes the affected hair follicles to be mistakenly attacked by a person’s own immune system

What is alopecia areata?

alopecia totalis; alopecia universalis

Alopecia areata that progresses to total scalp hair loss it is called ______________. When it results in complete body hair loss, it is called ____________.

postpartum alopecia; normal; 1 year

Jane, a client at your salon, gave birth to her first baby 3 months ago. When she comes in for a service, she complains that her hair seems to be shedding. This condition is called ___________. You reassure Jane that her hair growth cycle should eventually return to _______ within about _______.

minoxidil & finsateride

What are the only 2 products that have been proven to stimulate hair growth & are approved by the FDA for sale in the US?

minoxidil

A topical medication that is put on the scalp twice a day, & is sold over the counter as a nonprescription drug, is __________; the most commonly known product that contains this drug is called Rogaine.

finasteride

_____________ is an oral prescription medication for men only & is more effective & convenient that its nonprescription counterpart.

strong potential for birth defects

Why are pregnant women warned against having any contact with the oral prescription medication used to treat hair loss in men?

wigs, toupees, hair weavings, extensions

What non-medical options can a hairstylist offer to counter hair loss?

canities

technical term for gray hair

ringed hair

characterized by alternating bands of gray & pigmented hair

hypertrichosis

a condition of abnormal growth of hair

trichoptilosis

technical term for split ends

trichorrhexis nodosa

technical term for knotted hair

monilethrix

technical term for beaded hair

fragilitas crinium

technical term for brittle hair

congenital & acquired

What are the 2 types of canities?

anxiety; illness

In addition to genetics, _______ and _______ may also cause premature gray hair.

facial hair on women; electrolysis, photoepilation, laser hair removal, shaving, tweezing, electronic tweezers, depilators, epilators, threading, sugaring

What is an example of hypertrichosis? Name 5 of the 10 possible treatments?

trichorrhexis nodosa; trichoptilosis

Softening the hair with conditioners & moisturizers is often used in the treatment of ________ and may also help ___________, but will not repair split ends.

9 lbs

How many pounds of dead skin does the average person shed each year?

malassezia

Research confirms that dandruff is the results of a fungus called __________, a naturally occurring fungus that is present on all human skin.

pityriasis capitis simplex: scalp irritation, large flakes, itchy scalp

pityriasis steatoides: accumulation of greasy or waxy scales, mixed with sebum, that stick to the scalp in crusts

List the 2 principles types of dandruff & give their characteristics

pityriasis steatoides accompanied by redness & inflammation

What is seborrheic dermatitis?

True

True or False: Tinea is contagious

False

True or False: Ringworm is caused by a parasite

scutula

Which of the following conditions has a distinctive odor?

tinea barbae, scutula, scabies, head lice

pityriasis

technical term for dandruff

tinea

technical term for ringworm

tinea capitis

fungal infection characterized by red papules, or spots, at the opening of the hair follicles

tinea favosa

dry, sulfur-yellow, cuplike crusts on the scalp called scutula

scabies

caused by a parasite called a mite

pediculosis capitis

the infestation of the hair & scalp with head lice

furuncle

an acute, localized bacterial infection of the hair follicle

carbuncle

an inflammation of the subcutaneous tissue caused by staphylococci

thickness or diameter of individual hair strand

Define texture as it relates to hair analysis

the number of individual hair strands on one square inch of scalp

Define density as it relates to hair analysis

ability of hair to absorb moisture

Define porosity as it relates to hair analysis