Chapter 9 - Hair and Scalp Care

Disulfide bond

A chemical side bond that is very different from the physical bonding of a hydrogen or salt bond

Hypertrichosis

A condition of abnormal growth of hair

Polypeptide

A long chain of amino acids linked by peptide bonds is called a __________________

Dermal papilla

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

Arrector pili

A tiny, involuntary muscle in the base of the hair follicle

Cowlick

A tuft of hair that stands straight up

Hydrogen bond

A weak physical side bond

Salt bond

A weak temporary side bond between adjacent polypeptide chains

Alopecia

Abnormal hair loss is called __________

Furuncle

Boil, acute localized bacterial infection of the hair follicle

Anagan phase

Growth phase, new hair is produced

Hair stream

Hair flowing in the same direction

90 percent

Hair is approximately ____________ protein?

Whorl

Hair that forms in a circular pattern, as on the crown

Scabies

Highly contagious skin disease caused by a parasite called a "mite" that burrows under the skin

Carbuncle

Inflammation of the subcutaneous tissue caused by Staphylococci, similar to a furuncle but larger

Amino acids

Linked together end to end like pop beads

Hair density

Measures the number of individual hair strands on 1 square inch of scalp and is classified as low, medium or high

Hair root

Part of the hair located below the surface of the scalp

Hair shaft

Portion of the hair that projects above the skin

Keratinization

Process by which newly formed cells in the hair bulb mature, fill with keratin, move upward, lose their nucleus and die

Eumelanin

Provides brown and black color to hair

Pheomelanin

Provides colors ranging from red and ginger to yellow/blonde tones

Wave pattern

Refers to the shape of the hair strand and is described as straight, wavy, curly or extremely curly

Vellus

Short, fine and downy type of hair. Commonly found on infants

Monilethrix

Technical term for beaded hair

Fragilitas crinium

Technical term for brittle hair (two words)

Tinea

Technical term for ringworm

Trichoptilosis

Technical term for split ends

Postpartum alopecia

Temporary hair loss experienced at the conclusion of a pregnancy (two words)

Hair porosity

The ability of the hair to absorb moisture

Hair elasticity

The ability of the hair to stretch and return to its original length without breaking

Peptide bond or end bond

The chemical bond that links amino acids is called a ______________

COHNS elements

The five elements that make up human hair, skin, tissue and nails

Pediculosis capitis

The infestation of the hair and scalp with head lice (two words)

Medulla

The innermost layer and is composed of round cells

Terminal

The long hair found on the scalp, legs, arms and bodies of males and females

Pityriasis

The medical term for dandruff

Cortex

The middle layer of the hair

Sebaceous glands

The oil glands of the skin

Cuticle

The outermost layer of hair

Telogen phase

The resting or final phase in the hair cycle and lasts until the fully grown hair is shed

Trichology

The scientific study of hair and it's diseases and care

Sebum

The sebaceous glands secrete an oily substance called _________

Alopecia areata

The sudden falling out of hair in round patches or baldness in spots (two words)

Canities

The technical term for gray hair

Hair bulb

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

Hair texture

The thickness or diameter of the individual hair strand and is classified as coarse, medium or fine

Melanin

The tiny grains of pigment in the cortex that give natural color to the hair

Catagen phase

Transition period between the growth and resting phases of a hair follicle

Follicle

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

Anagen, catagen and telogen

What are the three hair growth stages?

Cuticle, cortex and medulla

What are the three main layers of the hair shaft?

Hydrogen, salt and disulfide bonds

What are the three types of side bonds

Vellus and terminal hair

What are the two main types of hair found on the body?

Medium hair texture

What hair texture is the most common?

Coarse hair

What hair type has the largest diameter?

Fine hair

What hair type has the smallest diameter and is more fragile?

Gray hair

What is caused by the absence of melanin?

One half inch

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