2. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Chapter 11 Properties of the Hair and Scalp

3. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Why study properties of the hair and scalp? You need to know how and why hair grows and how and why it falls out in order to be able to differentiate between normal and abnormal hair loss. Knowing what creates natural color and texture is a vital part if being able to offer a variety of chemical services to clients. Spotting an unhealthy scalp condition that could be harboring a communicable disease or even be causing permanent hair loss is a way to aid your client in caring for their scalp and hair’s well-being.

4. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Trichology Trichology: the scientific study of hair, its diseases, and its care. Derived from the Greek words trichos, meaning "hair” and ology, meaning "the study of." Integument: system includes hair, skin, nailsIntegument: Hair: slender, threadlike protein filament that is an appendage of the scalp and body. Composed of 2 parts: –Hair root: lies beneath the scalp –Hair shaft: projects above the scalp

5. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Healthy Hair We are what we eat. A healthy diet is necessary for healthy hair. Proper nutrients required. Hair made up of 20 amino acids. Body produces 11 of the 20. The remainder must come from diet. Proteins like meat, fish, eggs, and dairy products are good sources of amino acids, as are food combinations like peanut butter and bread, rice and beans, and beans and corn.

6. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Structure of Hair Root Follicle- the tube like depression, or pocket, in the skin that contains the hair root. –Distribution- hair found on entire body except soles of feet and palms of hands. –Growth- the follicle grows down from the epedrims into the dermis, and surrounds the dermal papilla. More than one hair can grow out of a follicle. Hair bulb-The lowest area or part of a hair strand. The lower part of the bulb fits over and covers the dermal papilla.

7. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Dermal papilla- A small, cone-shaped elevation located at the base of the hair follicle that fits into the hair bulb. It contains the blood and nerve supply that provides the nutrients needed for growth. Arrector piliArrector pili -A minute, involuntary muscle fiber in the skin inserted in the base of the hair follicle. Fear or cold causes it to contract, which makes the hair stand up straight, resulting in goose bumps. SEBACEOUS GLANDS: Oil glands of the skin, connected to the hair follicles. The sebaceous glands secrete an oily substance called sebum, which lubricates the hair and skin. Structure of Hair Root

8. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Structure of Hair Root

9. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Hair Shaft Structure HAIR SHAFT STRUCTURE: There are three main layers of the hair shaft Cuticle-The outermost layer of the hair. It consists of a single layer of transparent, scale like cells that overlap like shingles on a roof. A healthy, compact cuticle layer is the hair’s primary defense against damage.

10. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Cortex-The middle layer of hair; a fibrous protein core formed by elongated cells containing melanin pigment. About 90 percent of hair weight comes from the cortex. Protein structures located in the cortex provide hair elasticity. Changes resulting from chemical services occur in the cortex.

11. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Medulla- Innermost layer; also referred to as the pith of the hair. It is composed of round cells. Very fine and naturally blonde hair may not even have a medulla. Thick, coarse hair and beard hair always contain a medulla.

12. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Chemical Composition of Hair CHEMICAL COMPOSITION OF HAIR. Hair is composed of protein that grows from cells originating within the hair follicle. Keratinization:The process during which newly formed cells in the hair mature; they fill up with keratin, move upward, lose their molecules, and die. The hair shaft is a nonliving fiber composed of keratinized protein.Keratinization: Hair is 90 percent protein, in the form of long chains of amino acids made up of five elements.

13. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. COHNS Elements Carbon51 percent Oxygen21 percent Hydrogen6 percent Nitrogen17 percent Sulfur5 percent

14. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Amino Acids AMINO ACIDS. Units of structure that build proteins. Linked like pop beads Peptide or end bonds-Chemical bonds that link two amino acids. Polypeptide chain-A long chain of amino acids linked by peptide bonds. They intertwine with each other in a spiral shape called a helix. Helix- The spiral shape created when polypeptide chains intertwine with each other.

15. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part.

16. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Side Bonds of the Cortex SIDE BONDS OF THE CORTEX. The middle layer of hair is made up of millions of polypeptide chains. They are cross-linked like a ladder by three different types of bonds. The side bonds hold the keratin fibers in place and account for hair’s strength and elasticity. Hydrogen bonds Salt bonds Disulfide bonds

17. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part.

18. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Bonds of the Hair

19. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Hair Pigment HAIR PIGMENT. All natural hair color is the result of pigment located within the cortex. Melanin (tiny grains of pigment made from cells called melanocytes) they give natural haircolor. –Eumelanin (provides brown/black color) –Pheomelanin (provides yellow to red/ginger color) Natural hair color is the result of ratio of eumelanin to pheomelanin, along with the total number and size of pigment granules.

20. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Gray hair- Caused by the absence of melanin. It grows in exactly the same way as pigmented hair. Hair color versus haircolor- : Hair color (two words) refers to the color of hair created by nature. Haircolor (one word) is the term used in the beauty industry to refer to artificial haircoloring products.

21. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Wave Patterns WAVE PATTERNS: Refers to the shape of the hair strand and described as straight, wavy, curly, or extremely curly. Wave patterns are the result of genetics and racial background, although straight, wavy, and extremely curly hair exist in all races. Theoretically, it is now believed that natural curl is the result of one side of the hair strand growing faster than the other side, causing the long side to curl around the short side.

22. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Straight hair: Can be any type – fine or coarse, dense or thin – without regard to texture or density. It has a fairly regular and uniform diameter along a single strand. Cross sections of straight hair are usually round. Asian hair: Tends to be extremely straight.

23. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Wavy hair: Cross sections are usually oval and have a fairly regular and uniform diameter along a single strand. Caucasian hair: Tends to be straight to wavy.

24. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Extremely curly hair: Grows in long twisted spirals. Cross sections are highly oval and vary in shape and thickness along their length. Compared to straight or wavy hair, which tends to possess a fairly regular and uniform diameter along a single strand, extremely curly hair is fairly irregular, exhibiting varying diameters along a single strand. Some extremely curly hair, will coil like a phone cord. Extremely curly hair often has low elasticity, breaks easily, and has a tendency to knot on the ends. Gentle scalp manipulations, conditioning shampoo, and a detangling rinse help minimize tangles. African-American hair: Tends to be extremely curly.

25. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part.

26. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Types of Hair TYPE OF HAIR. The two main types of hair found on the body are vellus hair and terminal hair. Hormonal changes during puberty cause some areas of fine vellus hair to be replaced with thicker terminal hair. All hair follicles are capable of producing either vellus or terminal hair, depending on genetics, age, and hormones.

27. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. VELLUS (LANUGO) HAIR: Vellus hair is short, fine, and downy. It is not pigmented and almost never has a medulla. It is commonly found on infants and can be present on children until puberty. On adults, vellus hair is usually found in places that are normally considered hairless (forehead, eyelids, and bald scalp), as well as nearly all other areas of the body, except the palms of the hands and the soles of the feet. Women normally retain 55 percent more vellus hair than men. Vellus hair helps with the evaporation of perspiration.

28. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. TERMINAL HAIR: The long, coarse, pigmented hair found on the scalp, legs, arms, and bodies of males and females. Terminal hair is coarser than vellus hair, and, with the exception of gray hair, it is pigmented. It usually has a medulla.

29. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Growth Cycles of Hair Hair growth occurs in cycles. Each complete cycle has three phases that are repeated over and over again throughout life. The three phases are anagen, catagen, and telogen.

30. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Anagen: Growing phase. Hair grows for a period of two to six years, with an average growth of about 1/2 inch per month. At any one time, 90 percent of hair is growing. Duration of hair life is affected by gender, age, type of hair, heredity, nutrition, and health. Scalp hair grows faster on women than men. It grows faster between the ages of 15 and 30 and slows sharply after age 50. Growth Cycles of Hair

31. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Catagen: Transition phase. Ends the growth phase and lasts only one to two weeks.The follicle canal shrinks and detaches from the dermal papilla. The hair bulb disappears and the shrunken root end forms a rounded club. Less than 1 percent of the scalp hair is in the catagen phase at any one time. Growth Cycles of Hair

32. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Telogen: Resting phase. After catagen, the follicle begins a 3 to 6 month phase of resting. About 10 percent of hair is in the telogen phase at one time. After telogen, the cycle begins again. The entire growth cycle repeats itself every 4 to 5 years.

33. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Hair Growth Myths MYTHSFACTS Clipping, shaving, trimming, and cutting makes hair grow faster These grooming techniques have no effect on hair growth. Scalp massage increases hair growth. There is no evidence to indicate this is true. Minoxidil and Finasteride are the only treatments that have been proven to increase hair growth and are approved for that purpose by the Food and Drug Administration (FDA). Amount of natural curl is determined by racial background. Anyone of any race can have straight or extremely curly hair.

34. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Gray hair is coarser and more resistant than pigmented hair Other than lack of pigment, gray hair is exactly the same as pigmented hair. It is not more resistant than the pigmented hair on the same person’s head. Hair with round cross section is straight; hair with oval cross section is wavy; hair with flat cross section is curly. Cross sections of straight hair tend to be round and of curlier hair tend to be more oval, but cross sections of hair can be almost any shape, including triangular; the shape of the cross section does not always relate to the amount of curl or the shape of the follicle. The number of disulfide bonds in the strand determines the amount of curl.

35. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Hair Loss HAIR LOSS. Natural shedding of hair accounts for normal daily hair loss. Recent measurements indicate that the average rate of hair loss is about 35 to 40 hairs per day. Abnormal hair loss is called alopecia. The most common types are androgenetic alopecia, alopecia areata, and postpartum alopecia. Over 63 million people in the United States suffer from abnormal hair loss. Other types of alopecia are alopecia totalis and alopecia universalis

36. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Hair Loss Perceptions Recent studies show that, compared to men who have hair, bald men are perceived as: Less attractive Less assertive Less successful Less personally likeable Older by five years

37. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Emotional Impact of Severe Hair Loss Men –Negative social and emotional effects; preoccupation with baldness; effort made to conceal Women –Devastation; anxiety; feelings of helplessness and unattractiveness –As professional hairstylists, you may be one of the first to be asked for help, it is important to have an understanding of different types of hair loss and the products and services that are available.

38. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Androgenetic Alopecia A combination of heredity, hormones, and age causes progressive shrinking or miniaturization of terminal hair, converting it to vellus hair. Known as male pattern baldness in men. Can begin as early as teens; frequently seen by age 40. By age 35, almost 40 percent of men and women show some degree of loss. Gene can be inherited from either side of family. Affects millions of men and Women in the United States alone.

39. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Alopecia Areata Sudden loss in round or irregular patches. Affects five million people in the United States Autoimmune disorder that make our system attack the hair follicles. White blood cells stop the hair growth process during the anagen phase. Begins with small bald patches can progress to total scalp hair(totalis) or total body (universalis) Occurs in males and females of all ages and races, can begin in childhood No sign of scalp inflammation No obvious signs of skin disorder

40. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part.

41. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Postpartum Alopecia Temporary hair loss at conclusion of pregnancy Growth cycle returns to normal within one year after delivery of baby.

42. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Hair Loss Treatments Minoxidil: Topical medication applied to scalp twice daily; proven to stimulate hair growth. It is sold over the counter in two strengths: 2 percent regular and 5 percent extra strength; no known negative side effects. Most common product on market is Rogaine. Finasteride: Oral prescription for men only. Side effects include weight gain and loss of sexual function. Women may not use this treatment, and pregnant women or women who may become pregnant are cautioned not even to touch the tablets because of the strong potntial for birth defects.

43. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Hair Disorders Canities- technical term for grey hair.Caused by the loss of pigment in hair. Two types:Canities –Congenital canities- Exists at or before birth. Occurs mostly in albinos, occasionally in persons with normal hair. –Acquired canities- Usually due to old age; onset may occur prematurely in early adult life. Caused by worry, anxiety, nervous strain, prolonged illness.

44. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part.

45. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. RINGED HAIR: Alternating bands of gray and dark hair.

46. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. HYPERTRICHOSIS: Superfluous hair; also known as hirsuties; characterized by the growth of terminal hair in areas of body that normally only grow vellus hair. Can be tweezed or removed by depilatories, electrolysis, shaving, or epilation.

47. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. TRICHOPTILOSIS: technical term for split hair ends; can be treated with conditioner to lubricate and soften ends, the only way to remove spilt end is by cutting.

48. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. TRICHORRHEXIS NODOSA: Knotted hair; a dry, brittle condition including formation of nodular swellings along the hair shaft. The hair breaks easily, which creates a brushlike spreading of fibers along the hair shaft. Treated by softening the hair with conditioners and moisturizers. Hair Disorders (continued)

49. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. MONILETHRIX: Beaded hair; hair breaks between the beads or nodes. Can be treated with scalp and hair conditioning.

50. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. FRAGILITAS CRINIUM- Brittle hair, which causes splitting anywhere along the hair strand. Treated with hair and scalp conditioning or trimming above the split to prevent further damage.

51. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Scalp Disorders SCALP DISORDERS. Natural shedding of horny scalp scales occurs regularly and should not be mistaken for dandruff. The average person sheds about nine pounds of “dead” skin each year. DANDRUFF OR PITYRIASIS: Small white scales that usually appear on the scalp and hair. Characterized by excessive proliferation, shedding, and accumulation of surface cells. Recent research confirms that dandruff is not contagious.

52. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Pityriasis capitis simplex: Dry type. Characterized by itchy scalp and small white scales attached to scalp or scattered loosely in the hair. According to current research, caused by a fungus called malassezia that is present on all human skin, but develops into dandruff when it grows out of control. Treated through the use of mild or medicated shampoos, scalp treatments, regular scalp massage, daily use of antiseptic scalp lotions, and medicated scalp ointments. Pityriasis steatoides: Greasy or waxy type. Scales become mixed with sebum, causing them to stick to scalp in patches; medical treatment is advisable.

53. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Fungal Parasites Tinea- The technical term for ringworm. Caused by vegetable parasites; highly contagious. Begins with small reddened patch of little blisters; refer to a physician. Tinea capitis- Ringworm of the scalp; characterized by red papules or spots at opening of hair follicle; causes hair to break. Tinea favosa- Honeycomb ringworm; characterized by dry, sulfur-yellow, cuplike crusts on scalp called scutula; give off odor; scars from favus are pink or white, shiny bald patches. Very contagious and should be referred to a physician.

54. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Tinea favus Tinea Tinea capitis

55. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Parasitic Infections SCABIES (ITCH MITE): Highly contagious; vesicles and pustules from the irritation of the parasites or from scratching the affected area. PEDICULOSIS CAPITIS: Contagious condition caused by head lice infesting the hair and scalp; itching occurs and resultant scratching can cause infection. Refer to a physician.

56. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Staphylococci Infections STAPHYLOCOCCI INFECTIONS- Bacteria that infects the skin or scalp FURUNCLE OR BOIL: An acute staphylococci infection of a hair follicle that produces constant pain; produces a pustule perforated by a hair. Refer to a physician. CARBUNCLE: An inflammation of the subcutaneous tissue caused by staphylococci; similar to a furuncle but larger. Refer to a physician.

57. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Hair Analysis and Texture HAIR ANALYSIS: Hair analysis is performed by observation using the senses of sight, touch, hearing, and smell. The four most important factors to consider are texture, porosity, elasticity, and density. Other factors include natural growth pattern and degree of oiliness or dryness. HAIR TEXTURE: The thickness or diameter of the individual hair strand (NOTE: Compare a thin rope to a thick rope or a piece of thread to a piece of yarn).

58. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Coarse: Has the largest diameter; stronger than fine hair; usually requires more processing time and may be resistant to processing.

59. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Medium: The most common and is considered normal; does not pose any special problems. Thinner than coarse hairs and thicker than fine hairs.

60. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Fine: The smallest in diameter and the most fragile; easier to process; more susceptible to damage.

61. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Testing Hair Texture Hair texture can be determined by feeling a single strand between the fingers. Take an individual strand from the four different areas of the head- front hairline, temple, crown and nape. Hold securely with one hand while feeling it with the thumb and forefinger of the other.

62. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Hair Density HAIR DENSITY: Measures the number of individual hair strands on 1 square inch of the scalp. Low density –has fewer hairs on the hair usually coarse hair Medium – average thickness High –has more hair on the head usually fine hair Average: 2,200 hairs per square inch –Blond: 140,000 –Brown: 110,000 –Black: 108,000 –Red: 80,000

63. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Porosity POROSITY: The ability of the hair to absorb moisture; directly related to the condition of the cuticle layer. Low porosity: Hair considered resistant; requires more alkalinity in solutions.

64. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Average porosity: Normal hair; chemical services will usually process as expected.

65. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. High porosity: Overly porous hair; often the result of overprocessing; damaged, dry, fragile, and brittle. Chemical services require less alkaline solutions with a lower pH to prevent additional overprocessing.

66. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Testing for Porosity You can check for porosity on dry hair by taking several strands from the four different areas on the head. Hold several strands of hair securely in one hand while sliding your thumb and fore finger along the hair shaft from end to scalp. If the hair feels smooth and the cuticle is compact the hair is resistant. If the hair is slightly rough it is considered porous. If the hair feels very rough, dry, or breaks, it is considered highly porous and may be over processed.

67. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Elasticity Normal elasticity-Will stretch up to 50 percent of its original length when wet. Low elasticity-This hair is brittle, breaks easily, will not hold a curl; the result of weak side bonds, probably from overprocessing. ELASTICITY: The ability of the hair to stretch and return to its original length without breaking. It indicates the strength of the side bonds that hold the hair’s individual fibers in place.

68. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. To check the elasticity of one another’s hair by wetting a few hairs and taking an individual strand from four different areas of the head, as in the porosity test. Have them hold a single strand of wet hair securely and try to pull it apart. If the hair stretches and returns to its original length without breaking, it has normal elasticity. If it breaks or fails to return to original length, it has low elasticity. Have students discuss results.

69. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Growth Patterns Hair stream (hair flowing in same direction) resulting from the follicles slopping in same direction. Two streams flowing in different directions from the head form a natural part. Whorl (hair forms in a circular pattern) as on the crown. Cowlick (tuft of hair that stands straight up) usually more noticeable in the front hairline but they can be located anywhere on the head.

70. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Dry Hair and Scalp Dry hair and scalp can be caused by inactive sebaceous glands. With a lack of natural oils (sebum) hair appears dull, dry, lifeless. People with dry hair and scalp should avoid frequent shampooing, strong soaps, detergents, or products with a high alcohol content.

71. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Oily Hair and Scalp Characterized by greasy build up on the scalp and an oily coating on the hair, are caused by improper shampooing and overactive sebaceous glands. Use clarifying shampoos. Eat a well-balanced diet. Exercise. Shampoo regularly and frequently. Avoid strong soaps, detergents, or products with high alcohol content.

72. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Summary and Review Name and describe the five main structures of the hair root. Follicle: The tubelike 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 hair root. Dermal papilla: The small cone-shaped area located at the base of the hair follicle that fits into the hair bulb. It contains the blood and nerve supply for the hair. Arrector pili: Tiny, involuntary muscle fiber in the skin inserted at the base of the hair follicle; causes goose bumps. Sebaceous glands: Oil glands in the skin connected to hair follicles; they secrete an oily substance called sebum, which lubricates the hair and skin.

73. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Name and describe the three layers of the hair. Cuticle: Outermost layer of hair consisting of overlapping layers of transparent, scalelike cells that look like shingles on a roof. Cortex: The middle layer of fibrous protein core formed by elongated cells containing melanin pigment. Medulla: The innermost layer, composed of round cells; it is common for very fine and naturally blonde hair to lack a medulla layer. Describe the process of keratinization. As newly formed cells in the hair mature, they fill up with keratin, move upward, lose their nucleus, and die.

74. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. What are polypeptide chains? Polypeptide chains are long chains of amino acids linked by peptide bonds. Polypeptide chains are cross-linked like the rungs on a ladder by three different types of side bonds. These side bonds hold the polypeptide chains in place and account for the incredible strength and elasticity of human hair. Name and describe the two types of melanin responsible for natural hair color. Eumelanin provides brown and black color to hair. Pheomelanin provides hair colors from red and ginger to yellow/blonde tones.

75. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. List and describe the three types of side bonds. Which are permanent and which are temporary? Which are strongest and why? Hydrogen bonds: Physical side bonds that are easily broken by water or heat. They are weak individually, but because there are so many, they account for about one-third of the hair’s strength. Salt bonds: Weak, temporary cross-links that can be broken by changes in pH. Easily broken by strong alkaline or acidic solutions; account for about one-third of the hair’s overall strength. Disulfide bonds: Strong chemical side bonds that join sulfur atoms of two neighboring cysteine amino acids to create one cysteine, which joins together two polypeptide strands like rungs on a ladder. Summary and Review (continued)

76. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Name and describe the two types of hair and their locations on the body. Vellus, or lanugo, hair is short, fine, and downy. Found in places that are normally considered hairless, except the palms of the hands and soles of the feet. Terminal hair is the long, soft hair found on the scalp, legs, arms, and body. What are the three phases of the hair growth cycle and what occurs during each? Anagen, or growth, phase; New hair is synthesized. Catagen, or transition, phase; The brief transition period between the growth and resting phases of a hair follicle. Telogen, or resting, phase: The final phase in the hair cycle that lasts until the fully grown hair is shed. Summary and Review (continued)

77. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. What is the reason for normal daily hair loss? Normal daily hair loss is the natural result of the three phases of the hair’s growth cycle. The growth cycle provides for the continuous growth, fall, and replacement of individual hair strands. What are the most common types of abnormal hair loss? Androgenetic alopecia (result of genetics, age, and hormonal changes); alopecia areata (hair falling out in round patches or baldness in spots); and postpartum alopecia (experienced at the conclusion of a pregnancy).

78. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. What are the only two approved hair loss treatments? Minoxidil and Finasteride Name the two main types of dandruff and state whether either can be treated in the salon. Pityriasis capitis simplex can be treated in a salon with the use of mild or medicated shampoos, scalp treatments, regular scalp massage, daily use of antiseptic scalp lotions, and medicated scalp ointments. Pityriasis steatoides should be referred to a physician. Which scalp and hair disorders cannot be treated in the salon? Tinea capitis, tinea favosa, scabies, pediculosis capitis, furuncles, carbuncles. What four factors should be considered in hair analysis? Summary and Review (continued)

79. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. Which scalp and hair disorders cannot be treated in the salon? : Tinea capitis, tinea favosa, scabies, pediculosis capitis, furuncles, carbuncles. What four factors should be considered in hair analysis? Texture, porosity, elasticity, and density.

80. © Copyright 2012 Milady, a part of Cengage Learning. All Rights Reserved. May not be scanned, copied, or duplicated, or posted to a publicly accessible website, in whole or in part. You have completed one unit of study toward course completion. Congratulations!