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