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?
