Chapter 11 properties of the hair and scalp
How many hair growth treatments have been approved by the FDA for sale in the United States?
2
The average hair density is about how many hairs per square inch?
2,200
What is the approximate average rate of hair loss?
35 to 40 hairs per day
sebum
A fatty or oily substance secreted by the sebaceous glands that lubricates the skin.
keratin
A fibrous protein that grows from cells originating within the hair follicle.
polypeptide chain
A long chain of amino acids linked by peptide bonds.
salt bond
A weak, physical, cross-link side bond between adjacent polypeptide chains.
hydrogen bond
A weak, physical, cross-link side bond that is easily broken by water or heat.
Hair porosity
Ability of the hair to absorb moisture.
Hair elasticity
Ability of the hair to stretch and return to its original length without breaking.
alopecia
Abnormal hair loss.
peptide bond
Also known as an end bond; chemical bond that joins amino acids to each other, end-to-end, to form a polypeptide chain.
Androgenic alopecia
Also known as androgenetic alopecia (an-druh-je-NET-ik al-oh-PEE-shah); hair loss characterized by miniaturization of terminal hair that is converted to vellus hair; in men, it is known as male pattern baldness.
anagen phase
Also known as growth phase; phase during which new hair is produced.
Hypertrichosis
Also known as hirsuties (hur-SOO-shee-eez); condition of abnormal growth of hair, characterized by the growth of terminal hair in areas of the body that normally grow only vellus hair.
Vellus hair
Also known as lanugo hair; short, fine, unpigmented, and downy hair that appears on the body, with the exception of the palms of the hands and the soles of the feet.
telogen phase
Also known as resting phase; the final phase in the hair cycle that lasts until the fully grown hair is shed.
Tinea favosa
Also known as tinea favus; fungal infection characterized by dry, sulfur-yellow, cuplike crusts on the scalp called scutula.
Proteins are made of long chains of:
Amino acids
cystine
An amino acid formed when 2 cysteine amino acids (with single sulfur) are joined by their sulfur groups or disulfide bond.
cysteine
An amino acid with a sulfur atom (S) that joins together two peptide strands.
New hair is produced during the _____ phase, or growth phase, of hair growth.
Anagen
Which of the following statements is true?
Anyone of any race can have straight or extremely curly hair.
Alopecia areata
Autoimmune disorder that causes the affected hair follicles to be mistakenly attacked by a person's own immune system; usually begins with one or more small, round, smooth bald patches on the scalp.
furuncle
Boil; acute, localized bacterial infection of the hair follicle that produces constant pain.
side bonds
Bonds that cross-link the polypeptide chains together and are responsible for the extreme strength and elasticity of human hair.
Salt bonds can be broken by _____ solutions.
Both strong alkaline and strong acidic
The five major elements in skin and hair are referred to as the _____ elements.
COHNS
An inflammation of the subcutaneous tissue caused by staphylococci is called a _________.
Carbuncle
Alopecia areata most often begins during which stage of life?
Childhood
Hair that has the largest diameter and usually requires more processing time is:
Coarse
alopecia universalis
Complete loss of body hair.
Most of the total weight of hair comes from which layer of the hair?
Cortex
Which of the following is NOT one of the three types of side bonds of the cortex?
Cortex bonds
The measurement of the individual hair strands on 1 square inch of the scalp is hair:
Density
Thio neutralizers are used to reform _____ bonds.
Disulfide
Scutula
Dry, sulfur-yellow, cuplike crusts on the scalp in tinea favosa or tinea favus.
hydrophilic
Easily absorbs moisture; in chemistry terms, capable of combining with or attracting water (water-loving).
Hair with low elasticity:
Easily broken
The ability of the hair to stretch and return to its original length without breaking is called hair:
Elasticity
Unique protein structures within the cortex are responsible for the color and _____ of hair.
Elasticity
The cortex of the hair has a fibrous protein core formed by _____ cells.
Elongated
Peptide bonds are also known as:
End Bonds
______________ is an infection of the hair follicles frequently caused by staphylococcus or other bacteria.
Folliculitis
An acute, localized bacterial infection of a hair follicle that produces constant pain, is called a boil or a:
Furuncle
Which of the following causes androgenetic alopecia?
Genetics, age and hormonal changes
Canities is the technical term for:
Gray hair
The thickened, club-shaped structure that forms the lower part of the hair root is the:
Hair bulb
Which of the following is NOT one of the four most important factors to consider in hair analysis?
Hair color
Which layer of hair consists of transparent, scale-like cells?
Hair cuticle
Which layer of hair provides a barrier that protects the inner structure of hair?
Hair cuticle
hair stream
Hair flowing in the same direction, resulting from follicles sloping in the same direction.
The _____ is the tube-like depression in the skin or scalp that contains the hair root.
Hair follicle
The two parts of a mature strand of human hair are:
Hair root and hair shaft
The portion of the hair that projects above the skin is the:
Hair shaft
Whorl
Hair that forms in a circular pattern on the crown of the head.
Which of the following is a nonsurgical option for hair loss that is available in a salon setting?
Hair weaving
Which type of side bond can be broken by water or heat?
Hydrogen
Porous hair has a raised cuticle layer that easily absorbs moisture and is called:
Hydrophilic
A mustache or light beard on a woman is an example of what condition?
Hypertrichosis
Pediculosis capitis
Infestation of the hair and scalp with head lice.
Carbuncle
Inflammation of the subcutaneous tissue caused by staphylococci; similar to a furuncle but larger.
medulla
Innermost layer of the hair that is composed of round cells; often absent in fine and naturally blond hair.
The maturing process of hair is:
Keratinization
Trichorrhexis nodosa is the technical term for:
Knotted Hair
Terminal hair
Long, coarse, pigmented hair found on the scalp, legs, arms, and bodies of males and females.
Proteins
Long, coiled complex polypeptides made of amino acids.
hair bulb
Lowest part of a hair strand; the thickened, club-shaped structure that forms the lower part of the hair root.
____________ is a naturally occurring fungus that is present on all human skin.
Malassezia
Vellus hair almost never has a:
Medulla
cortex
Middle layer of the hair; a fibrous protein core formed by elongated cells containing melanin pigment.
Malassezia
Naturally occurring fungus that is present on all human skin, but is responsible for dandruff when it grows out of control.
hydrophobic
Naturally resistant to being penetrated by moisture.
A study suggests that bald men are perceived as:
Older
Disulfide bonds account for about _____ of the hair's overall strength.
One-third
hair cuticle
Outermost layer of hair; consisting of a single, overlapping layer of transparent, scale-like cells that look like shingles on a roof.
Hair follicles are distributed all over the body, with the exception of the:
Palms and soles of the feet
The infestation of the hair and scalp with head lice is also known as:
Pediculosis capitis
Amino acids are joined by _____ bonds.
Peptide
A severe type of dandruff characterized by an accumulation of greasy or waxy scalp scales mixed with sebum is:
Pityriasis steatoides
dermal papilla
Plural: dermal papillae. A small, cone-shaped elevation located at the base of the hair follicle that fits into the hair bulb.
The ability of the hair to absorb moisture is called hair:
Porosity
keratinization
Process by which newly formed cells in the hair bulb mature, fill with keratin, move upward, lose their nucleus, and die.
Hair is approximately 90 percent:
Protein
Eumelanin
Provides natural dark brown to black color to the hair and is the dark pigment predominant in black and brunette hair.
Pheomelanin provides hair colors ranging from:
Red to Blond
The medulla is composed of _____ cells.
Round
When a parasite called a mite burrows under the skin, the result is:
Scabies
Trichology
Scientific study of hair and its diseases and care.
Pityriasis steatoides
Severe case of dandruff characterized by an accumulation of greasy or waxy scales mixed with sebum that stick to the scalp in crusts.
The wave pattern of the hair refers to the ______ of the hair strand.
Shape
helix
Spiral shape of a coiled protein created by polypeptide chains that intertwine with each other.
A helix is:
Spiral shaped
What is trichoptilosis?
Split ends
disulfide bond
Strong chemical side bond that joins the sulfur atoms of two neighboring cysteine amino acids to create one cystine, which joins together two polypeptide strands like rungs on a ladder.
Monilethrix
Technical term for beaded hair.
Fragilitas crinium
Technical term for brittle hair.
Pityriasis capitis simplex
Technical term for classic dandruff; characterized by scalp irritation, large flakes, and itchy scalp.
Pityriasis
Technical term for dandruff; characterized by excessive production and accumulation of skin cells.
Canities
Technical term for gray hair; results from the loss of the hair's natural melanin pigment.
Trichorrhexis nodosa
Technical term for knotted hair; it is characterized by brittleness and the formation of nodular swellings along the hair shaft.
Tinea
Technical term for ringworm—a contagious condition caused by fungal infection and not a parasite; characterized by itching, scales, and, sometimes, painful lesions.
Trichoptilosis
Technical term for split ends.
The final phase in the hair cycle, lasting until the fully grown hair is shed, is the _____ phase.
Telogen phase
Postpartum alopecia
Temporary hair loss experienced towards the end and after the pregnancy.
Hair _____ is the thickness or diameter of the individual hair strand.
Texture
lanthionine bonds
The bonds created when disulfide bonds are broken by hydroxide chemical hair relaxers after the relaxer is rinsed from the hair.
catagen phase
The brief transition period between the growth and resting phases of a hair follicle. It signals the end of the growth phase.
COHNS elements
The five elements—carbon, oxygen, hydrogen, nitrogen, and sulfur—that make up human hair, skin, tissue, and nails.
Pheomelanin
The lighter pigment that provides natural colors ranging from red and ginger to yellow and blond tones.
Hair density
The number of individual hair strands on 1 square inch (2.5 square centimeters) of scalp.
Sebaceous glands
The oil glands in the skin that are connected to the hair follicles.
hair root
The part of the hair located below the surface of the epidermis.
hair shaft
The portion of hair that projects above the epidermis.
wave pattern
The shape of the hair strands; described as straight, wavy, curly, and extremely curly.
arrector pili muscle
The small, involuntary muscle in the base of the hair follicle.
Melanin
The tiny grains of pigment in the cortex that give natural color to the hair.
hair follicle
The tube-like depression or pocket in the skin or scalp that contains the hair root.
Generally, only which type of hair contains a medulla?
Thick, coarse hair
Hair texture
Thickness or diameter of the individual hair strand.
Which condition is characterized by dry, sulfur-yellow, cuplike crusts on the scalp?
Tinea favosa
alopecia totalis
Total loss of scalp hair.
Cowlick
Tuft of hair that stands straight up.
amino acids
Units that are joined together end-to-end like pop beads by strong, chemical peptide bonds (end bonds) to form the polypeptide chains that comprise proteins.
Ringed hair
Variety of canities characterized by alternating bands of gray and pigmented hair throughout the length of the hair strand.
Hair that forms a circular growing pattern, as on the crown of the head, is called a:
Whorl
The term used to describe abnormal hair loss is:
alopecia
Which of the following conditions is an autoimmune disorder?
alopecia areata
The technical term used to describe gray hair is:
canities
The small, cone-shaped area at the base of the hair follicle that fits into the hair bulb is the:
dermal papilla
The technical term for brittle hair is:
fragilitas crinium
Extremely curly hair does NOT typically:
have a fairly regular and uniform diameter along a single strand
The condition that describes abnormal growth of hair is:
hypertrichosis
Oily hair and scalp can be caused by:
improper shampooing
Hydroxide chemical hair relaxers break disulfide bonds and convert them to
lanthionine bonds
Research has determined that dandruff is the result of a fungus called:
malassezia
Scabies is a type of____________:
parasitic infection
The condition characterized by the excessive production and accumulation of skin cells is:
pityriasis
The two types of dandruff are_____________:
pityriasis capitis simplex and pityriasis steatoides
Which type of alopecia describes temporary hair loss at the end of a pregnancy?
postpartum alopecia
Alternating bands of gray and pigmented hair throughout the length of the hair strand is called:
ringed hair
Polypeptide chains are cross-linked like the rungs on a ladder by _____ different types of side bonds.
three
A fungal infection characterized by itching, scales, and sometimes painful circular legions is:
tinea
People with dry hair and scalp should:
use products containing emollients