1. Properties Of The Hair And Scalp
In some primitive societies the hair was often and indicator of rank. American Indians are well known for the distinctive ways of wearing their hair. The Australian aborigine wailed and tore at the hair when a close member of the tribe died. In New Guinea, the males make a great display of their headdress. In islands of the Pacific, warriors have huge bushy hairdos of which they are very proud.
These customs are the opposite of our usual habits because we find it is the females who usually have the gaudy, colorful hair fashions in our community. But a look at the pages of history shows that this was not always the case. Once, it was the man who powdered and perfumed his long locks.
Biologically, there is a difference in the length of hair between sexes. If the hair is left uncut, the female usually has the longer hair of the two. We have no real explanation for this. Humorously, it has been claimed the reason may well be that when our cavemen forefathers sought a wife, women with longer hair were more easily caught.
Today, we have a situation in which the care of the hair is of ever growing importance to our economy. Millions of dollars are spent annually on the hair and its care. The beauty industry employs thousands of workers and indirectly are partly responsible for the ever increasing productivity of the country, because if we look better, we also work much better.
Lastly, we must not overlook the benefits of the good mental health and well-being of the community. This is assisted by the work of the artisan who gives professional attention to the properties and condition of the hair.
The most important task of the hair is to assist the skin in protecting certain areas of the body. In fact, hair may be regarded as a specialized form of skin which, for the purpose of protection, has a more effective structure. The value of hair protection can be quickly recognized. The brain can be regarded as the most delicate and essential organ of the body. A thick head of hair serves as a cushion to a possible bump on the head and possible injury to the brain.
Over the ages, man has experienced a general reduction in body hair. However, this is not true in the case of the scalp. This suggests that scalp hair still has a very important protective purpose. The eyes are protected by the hairs of the eyelashes and the eyebrows. The ears and nose have special hairs which line the passages of these organs. The body is protected from friction, caused by muscular movements and the wearing of clothing. The hair also aids in the evaporation of sweat..

2. Lesson Objectives After completing this chapter, you will be able to:
Name and describe the structures of the hair root.
List and describe the three layers of the hair.
Describe the three types of side bonds in the cortex.
List the factors that should be considered in hair analysis.
Describe the process of hair growth.
Discuss the types of hair loss and their causes.
Describe the options for hair loss treatment.
Recognize hair and scalp disorders commonly seen in the salon and school, and know which can be treated by cosmetologists.

3. From Lady Godiva’s infamous horseback ride, to all the sought-after celebrity styles that make headlines every day, hair has been one of humanity’s most enduring obsessions.
So familiar and so surprising, so simple in appearance and yet the object of such advanced scientific and technological research. The term “crowning glory” aptly describes the importance placed on hair, such as how good we feel when our hair looks great, and just how distressing a “bad hair day” can be. This is why hair stylists play such an important role.
As has always been the case in every country since history began, hair still possesses powerful symbolic and evocative properties. An object of traditions and beliefs, a sign with hierarchical, religious or mystical significance, it also indicates an established order or a refusal to comply with one. In addition, it is a means of projecting the image we have of ourselves and in fact plays multiple roles. It is not therefore by chance that hair has taken such an important place in everyday language.
As fascinating as hair styling may be, all professional hair services need to be based on a thorough understanding of the growth, structure, and composition of hair. It is the only way to know why hair grows and why it falls out, what creates natural color and texture, and how to spot an unhealthy scalp condition that could be harboring a communicable disease or even be causing permanent hair loss.
Whereas the hair has always been the focus of all kinds of attention, beliefs and traditions throughout the world, this phenomenon once considered to be 'a type of plant growing on the head', remained overlooked by science for far too long. But all that has changed. Driven by the efforts of major groups, hair is studied in laboratories and day by day, often after very long periods of research, a whole wealth of fascinating discoveries and inventions are introduced.

4. The scientific study of the hair, and its diseases and care, is called trichology, which comes from the Greek work trichos (hair) and ology (the study of).
As a cosmetologist, you will need to know as much as you can about the structure of the hair, and how to keep it healthy. The more you learn, the more you will understand how salon services affect different hair types. That’s the key to consistent results from your services and happy clients who recommend you to others.
Hair is incredibly strong. Each hair can withstand the strain of 100 grams, meaning that an average head of 120,000 hairs could cope with 12 tons, if the scalp were strong enough!

5. The hair, skin, and nails are known collectively as the integumentary system, which is the largest and fastest growing organ of the human body.

6. STRUCTURES OF THE HAIR ROOT
FOLLICLE BULB PAPILLA ARRECTOR PILI MUSCLE SEBACEOUS GLANDS

7. Composite Model – Hair Follicle
Follicle - The tube like depression, or pocket, in the skin or scalp that contains the hair root.
Distribution - Hair is found over the entire body except on the soles of feet and palms of hands.
Growth - Follicle grows downward from the epidermis into the dermis, where it surrounds the dermal papilla. More than one hair can grow from a single follicle.
You will note that there is no break or hole in the epidermis into the formation of the follicle. The epidermis of the follicle lacks the dry, scaly nature seen on the upper, outer layers. If you pluck a hair out of its follicle, some of the follicle wall tears away. This is what you see as a whitish blob of soft tissue at the bottom of the hair.
Nearly the entire surface of the skin is covered with thousands and thousands of follicles. Most of them remain inactive and never produce hairs. On the other hand, some are very active like those on the scalp. Other follicles may only produce hair at a definite period in our lives (e.g., beard follicles of adult males). Still others will produce hairs in certain abnormal situations (e.g., one the face of women suffering from a disturbance of glands). Follicles are not scattered evenly on the scalp. The direction of each follicle plays a role in the texture of the hair. Most follicles emerge at an angle from the skin which is not the same for all follicles. This creates natural parts, cowlicks, widow’s peaks, and whorls.
Composite Model – Hair Follicle

8. Hair bulb - The lowest area or part of a hair strand
Hair bulb - The lowest area or part of a hair strand. It is the thickened, club shaped structure that forms the lower part of the hair root. The lower part of the bulb fits over and covers the dermal papilla.
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.
The bulb is firmly clamped or anchored over the papilla. This and the narrowness of the follicle, prevents the hair from being pulled out easily.
The papilla is an up-growth of the dermis at the bottom of the follicle. If the papilla is destroyed, the hair will never grow again.
The papilla is an essential structure and hair owes its very existence to its activity.
The hair is not like a plant growing in the soil with an independent life of its own, but is a special part of the skin which is growing outwards.

9. Arrector Pili - 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.”
Since man has lost most of his body hair, this is now a rather ineffective way of combating coldness. The hairs are trying to create a blanket of warmth, still air around the body in a manner similar to birds that fluff out their feathers on a cold day.

10. 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.
The sebaceous glands, next to the hair follicle, supply the sebum. This mixture of triglycerides, waxes and squalene form a film on the surface of the skin and lubricate the hair, thus preserving its suppleness and sheen. Being hormone dependent, the sebum can be produced in excessive quantities, making the hair greasy and heavy. On the other hand, if too little is secreted, the hair becomes damaged, dry and dull.

12. Zoom Into Hair

13. Structures Of The Hair Shaft
Cuticle
Cortex
Medulla

14. Cuticle - The outermost layer of the hair
Cuticle - The outermost layer of the hair. It consists of a single, overlapping 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. The cuticle is responsible for shiny hair!
The cuticle´s primary function is to prevent the inner structures of the hair shaft from losing moisture. The cuticle serves to create a barrier from elements, chemicals, other liquids, and heat. Another important function of the cuticle is to act as an indicator to the health of your hair. An intact cuticle feels smooth and silky while a damaged cuticle feels brittle and rough.
To feel the cuticle, pinch a single strand of hair between your fingers. Pull downward and it feels sleek and smooth. Now, pinch the end of the hair strand and move up the hair strand. The hair will feel rougher because you are going against the natural growth of the cuticle layer.
A healthy cuticle layer protects the hair from penetration and prevents damage to the hair fibers. Oxidation hair colors, permanent waving solutions, and chemical hair relaxers must have an alkaline pH in order to penetrate the cuticle layer, because a high pH (alkaline) swells the cuticle causing it to lift and expose the cortex.
Under the electronic microscope, the scales making up the cuticle appear to be a firmly held together by a cement rich in lipids. By transposing work carried out on the intercellular cement of the skin's corneous layer to hair, researchers were on the track of certain lipids - the ceramides. They discovered that these lipids play a major role in keeping the scales in place. In order to be certain, researchers closely examined damaged hair - where they found confirmation, under the microscope, that in these hairs, the ceramides had disappeared.

15. Cortex - The middle layer of hair; a fibrous protein core formed by elongated cells containing melanin pigment. About 90% of hair weight comes from the cortex. Protein structures located in the cortex provide hair elasticity.
When the cortex is exposed due to cuticle damage, the hair tends to be dry and dull looking. The hair fiber is susceptible to damage when cuticle breakage occurs. Hair becomes weak, unmanageable, brittle, and lifeless. The physical properties of the hair which depend on the cortex are: strength, elasticity, pliability, diameter, texture, and quality. A single strand of hair in good condition, will support a weight of 5-7 oz.
The changes involved haircoloring, perming, wet setting, thermal styling, and relaxing all take place in the cortex.

16. Medulla - Innermost layer; also referred to as the pith or marrow 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.
The innermost layer, known as the medulla, can be described as a hollow, small core of round cells running through the length of the hair strand. The fragmented, or disconnected cells of the medulla are composed of proteins. Functions of the inner layer are limited. However, the medulla may play a role in the reflection of light.
It is uncommon for very fine and naturally blond hair to have a medulla. Generally, only thick, coarse hair contains a medulla. Beard hair also contains a medulla. Lanugo hair has no medulla.
The medulla is not involved in salon services. Some think that the state of health and taking of certain medications has a direct bearing on its absence. Hair does not seem to suffer in its absence.

17. CHEMICAL COMPOSITION OF HAIR - Hair is composed (90%) of protein called keratin 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 non-living fiber.
To stay looking beautiful and ensure its strength, hair needs lipids. Some are a constituent part of the hair shaft, others are supplied to it by the sebaceous glands. The lipid components of hair represent 3% of its composition. Produced in the hair bulb they are formed from sterols , fatty acids and ceramides. They are present essentially in the intercellular cement of the cortex and the cuticle and provide the hair with a certain impermeability and ensure the cohesion of the capillary fiber.

18. COHNS ELEMENTS Make up the protein (keratin)
Carbon - 51%
Oxygen - 21%
Hydrogen - 6%
Nitrogen - 17%
Sulfur - 5%
Apart from water which, under normal conditions, accounts for 12% to 15% of the composition of hair, still other elements are also present in small quantities. Some of these are provided by the environment. Thus its relative porosity that allows it to take up water or water vapor in considerable quantities and trap the mineral salts in it. These form an integral part of the hair shaft. Others come directly from our body. Since the hair root has a good blood supply, substances from the blood are incorporated into the hair during its formation. Because of this, a hair can supply a great deal of information about its "owner" and, without exaggerating, we really can now say that hair has become a real "informer".
The five major elements found in the hair, skin, and nails are the COHNS elements. The exact composition varies widely with the type of hair, depending to a large extent on age, race, sex, and color. The resistant properties of the hair are due to its relatively high sulphur content. The hair that contains the largest amount of sulphur is red hair making it the strongest type of hair.
Hair is an organic substance and will burn or singe readily. It gives off a strong characteristic odor due to the protein or nitrogen present.

19. Proteins are made of long chains of amino acids that are linked together end to end like pop beads
Peptide (or end) bonds - The chemical bond that joins the amino acids to each other.
Polypeptide chain - A long chain of amino acids linked by peptide bonds. They intertwine around each other in a spiral shape called a helix.

20. HYDROGEN SALT DISULFIDE
SIDE BONDS OF 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.
HYDROGEN SALT DISULFIDE
It's like a building set. Composed of several elements, assembled by putting them together to obtain a shape. If we don't like the shape, we dismantle the elements, move them around, reassemble them and create another shape. A set like this exists within the minute body of the hair, where the elements in question are molecules and the links chemical bonds. It is the hair's keratin structure which enables it to adopt such a wide variety of forms. This protein is a long chain of amino acids which in the hair is made up of four twisted chains running lengthways. Chemical bonds are established between the atoms in these chains which provide the cohesion of the whole, thereby giving the hair its natural form. By acting on these more or less resistant bonds, the hair's form can be altered in a temporary or more long-lasting manner. So that if, for example, we go to bed with wet hair, this form will be haphazard, giving the hair an unkempt appearance. On the other hand, blow-drying or setting gives us control of the process so that, once dry, the hair will retain the form it has been given. In both cases, this form is only temporary. The first reason is quite logical, since any renewed presence of water will result in breaking these newly formed bonds. The other reason is that there are other, more resilient bonds within the hair which will gradually give it back its original form. These are the bonds that must be altered if a more long-lasting modification of the hair's shape is to be achieved.

21. The cortex
The cortex is a tight spiral of long proteins twisting like the curly cord on a telephone. The cortex gives hair its elasticity. When you stretch a hair, you straighten the coiled proteins in the cortex. When you release the hair, the proteins coil up again. The pigments that give your hair its natural color are sitting inside the cortex and are protected from the elements by the translucent layer of cuticle cells.
The cortex sits inside the transparent sheath of cells formed by the cuticle.

22. Hydrogen bonds - A physical side bond that is 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.

23. Salt bonds - A physical side bond that is broken by changes in pH
Salt bonds - A physical side bond that is broken by changes in pH. Easily broken by strong alkaline or acidic solutions; account for about one-third of the hair’s overall strength.

24. Disulfide bonds -A chemical side bond that differs greatly from the physical side bonds. Disulfide bonds join sulfur atoms of two neighboring cysteine amino acids to create cystine. There are far fewer than the physical bonds, but they are stronger and account for about one-third of the hair’s overall strength giving the hair its strength and elasticity. These bonds are broken and reformed during permanent waving and chemical relaxing. If these bonds are destroyed so is the hair!
Thio permanent waves break disulfide bonds, which are re-formed by thio neutralizers. Hydroxide chemical hair relaxers break disulfide and then convert them into lanthionine bonds when the relaxer is rinsed from the hair. Bonds broken by hydroxide relaxers are broken permanently and can never be reformed.
Chemical bonds are called "bridges", which is a clear indication of their resilience. They are disulphide bridges , acting on the sulfurated elements in the keratin . Resistant to water, they can only be broken by using chemical compounds. When they have been broken, the keratin chains can be moved and the hair becomes malleable. Hair considered too straight may then be curled - this is permanent waving. On the other hand, hair considered too curly or frizzy can be straightened out - this is uncurling. The result is made long-lasting by using another compound to re-establish the disulphide bridges according to the new position of the keratin chains, thereby determining the hair's new form.

25. BOND TYPE STRENGTH BROKEN BY REFORMED BY
HYDROGEN
Side Bond
Weak physical
Water, heat, or tension
Drying, cooling, or tension
Salt
Changes in pH
pH normalizer
Disulfide
Strong chemical
1. Thio perms and relaxers 2. Hydroxide relaxers
1. Oxidation with neutralizer 2. Conversion to lanthionine
Peptide
End Bond
Strong Chemical
Chemical Depilatories
Not reformed; hair dissolves

26. a) Eumelanin - Provides brown and black color to hair.
HAIR PIGMENT - All natural hair color is the result of pigment located within the cortex.
1. Melanin - The tiny grains of pigment in the cortex that give natural color to hair.
a) Eumelanin - Provides brown and black color to hair.
b) Pheomelanin - Provides natural hair colors from red and ginger to yellow-blonde tones.
Melanin is responsible for the natural color of hair. Produced deep in the root by the melanocytes, it is then transmitted to the keratinocyte as the hair is formed. Meaning that hair is colored right from the outset. The immense range of natural hair color is absolutely astonishing. However, melanin only represents 1% of the total composition of the hair and only exists in the form of two pigments: eumelanin, dark, and phaeomelanin, light.
Blonde Hair
Black Hair
Brown Hair

27. Natural hair color Is the result of the ratio of eumelanin to pheomelanin, along with the total number and size of pigment granules.
Gray hair is caused by the absence of melanin. It grows in exactly the same way as pigmented hair but without the melanin pigment.
Pheomelanin
Eumelanin

28. HAIRCOLOR VS. HAIR COLOR - 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.

29. WAVE PATTERN AND TENDENCIES
Described as straight, wavy, curly, or extremely curly. Wave pattern is the result of genetics and racial background.
Straight hair - Can be any type without regard to texture or density. It can be fine or coarse, dense or thin. It has a fairly regular and uniform diameter along a single strand. Cross-sections of straight hair are usually round.
Natural wave patterns are the result of genetics. The wave pattern can also vary from strand to strand on the same person’s head. Individuals with curly hair often have straighter hair in the crown and curlier hair in other areas.

30. Wavy Hair - Cross-sections are usually oval and have a fairly regular and uniform diameter along a single strand.
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, extremely curly hair is quite irregular showing varying diameters along a single strand.
Several theories attempt to explain the cause of natural curly hair. The most popular theory claims that the shape of the shape of the hair’s cross section determines the amount of curl. At present, natural curl is believed to be the result of one side of the hair growing faster than the other. The side that grows fastest will be longer than the other side. Tension within the strand causes the long side to curl around the short side. Hair that grows uniformly on both sides does not create tension and results in straight hair. This theory is still unproven.
Some extremely curly hair has a natural tendency to form a coil. Coiled hair usually has a fine texture, with many individual strands winding together to form coiled locks. Extremely curly hair often has low elasticity, breaks easily, and has a tendency to knot, esp. on the ends.

31. Results of Follicle Shape Results of Follicle Size
Asians - Tend to have extremely straight hair.
Caucasians - Tend to have straight to wavy hair.
African-Americans - Tend to have extremely curly hair. Remember, however, that straight, curly and extremely curly hair exist in all races.
Results of Follicle Shape
It is quite obvious that no particular ethnic group has any advantages when it comes to hair. On the other hand, each group can be associated with a certain type of hair, easily identifiable by its color and form, but also by something less obvious to the naked eye - the way it grows. Classifying hair into no more than three ethnic types - African hair, Asian hair, or Caucasian hair - might seem an exaggerated simplification. But it is true that Japanese hair is not the same as Indonesian hair and, even more obvious, Scottish hair has no resemblance to Swedish hair or Sicilian hair. However, these are only small differences in comparison with the similarities that each ethnic group has in general terms. Whether it is a question of the hair's density, speed of growth or the implantation of the hair follicle in the scalp, we can consider that each of the ethnic types mentioned above has its own identity. For example, Asian hair holds the speed record for growth with 1.3 cm a month. On the other hand, it has lower density than any of the other ethnic groups. The way its follicle is implanted causes the hair to grow straight, perpendicular to the scalp. African hair, generally black hair, is the slowest growing of all, at less than 0.9 cm a month. On the other hand it is slightly more dense than Asian hair and grows almost parallel to the scalp, twisting around itself as it grows. As far as rate of growth is concerned, Caucasian hair comes between the other two at 1.2 cm a month, but it has the highest density of all. It grows at an oblique angle to the scalp and is slightly curved.
Results of Follicle Size

32. 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.
All salon services must begin with a thorough analysis of the client’s hair type and its present condition in order to determine the results than can reasonably be expected from the service. Because different types of hair react differently to the same service, it is essential that a thorough analysis be performed prior to all services!

33. Hair Texture
The thickness or diameter of the individual hair strand (compare a thin rope to a thick rope or a piece of thread to a piece of yarn).
Coarse - Has the largest diameter; stronger than fine hair; usually requires more processing time and may be resistant to processing.
Medium -The most common and is considered normal; does not pose any special problems. It is thinner than coarse hair and thicker than fine hair.
Fine -The smallest diameter and is more fragile; easier to process; more susceptible to damage.
Hair texture can vary from strand to strand on the same person’s head. It is not uncommon for hair from different areas of the head to have different textures. Hair from the nape, crown, temples, and front hairline usually have a different texture than the remainder of the hair.

34. The hair type is very important in determining how well a perm will hold and how much color can be deposited into the hair shaft.
Fine, thin hair usually has a lower cortex to cuticle ratio. This usually means there are less Disulfide bonds to be broken and thus less to be reformed which many times is the cause of fine hair not holding perms as long as other hair types. The fade in color can also be to some degree attributed to the cortex to cuticle ratio. The less cortex, the less area for color to be deposited and the less salt bonds available in the cortex for the color molecules to attach themselves.

35. strands. Number varies by hair color.
Hair density - Measures the number of individual hair strands on one square inch of the scalp.
Low - Thin hair
Medium - Average or normal
High - Dense or thick hair
Average hairs/square inch. Average head of hair contains about 100,000 individual hair
strands. Number varies by hair color.
Blonde - 140,000
Brown - 110,000
Black - 108,000
Red - 80,000

36. Resistant Cuticle - Low Porosity
Porosity - The ability of the hair to absorb moisture; directly related to condition of the cuticle layer.
Low porosity- Considered resistant; requires more alkaline solutions and a longer processing time.
Resistant Cuticle - Low Porosity

37. High/Extreme Porosity
Average porosity -Normal hair; chemical services will process as expected.
High porosity -Overly porous; often the result of over processing; damaged, dry, fragile, & brittle. Chemical services require less alkaline solutions (lower pH prevents additional over processing) and shorter processing time.
High/Extreme Porosity

38. Hair broken from rubber band use.

39. Check the porosity of the hair by taking a strand of hair from four different areas of the head: the front hairline, the temple, the crown and the nape. Hold the strand securely with one hand while sliding the thumb and forefinger of the other hand form the end to the scalp. If the hair feels smooth and the cuticle is compact, dense, and hard, it is considered resistant. If the strand ruffles or you feel roughness, the hair is considered porous. If it feels very rough, dry, or breaks, it is considered overly porous.

40. 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.
Normal elasticity - stretches up to 50% of its original length when wet.
Low elasticity - hair is brittle and breaks easily; will not hold a curl; the result of weak side bonds, probably as a result of over-processing.
Hair with good elasticity will hold wet sets and perms longer. Fine hair does not have good elasticity, which is the reason it does not hold curl well. Damaged hair has poor elasticity.

41. Check the elasticity of one hair by wetting a few hairs and taking an individual strand from four different areas of the head as in the porosity test. Hold a single strand of wet hair securely and pull it. 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.

42. GROWTH PATTERNS
Hair stream - Hair flowing in the same direction; result of follicles sloping in the same direction. Two streams flowing in opposite directions create a natural part.
Whorl - Hair that forms a circular pattern, as on the crown.
Cowlick - A tuft of hair that stands straight up; can be found anywhere but are more noticeable on the hairline.

43. Dry hair and scalp - inactive sebaceous glands; aggravated by dry winter or desert climate.
1. dull, dry, lifeless.
2. avoid frequent shampooing and strong soaps, detergents, or products with high alcohol content.
Oily hair and scalp - overactive sebaceous glands; greasy buildup on scalp and oily coating on hair.
1. Clarifying shampoos
2. Well-balanced diet
3. Exercise
4. Regular, frequent shampooing; good personal hygiene; avoid strong soaps, detergents, or products with high alcohol content.

44. TYPES OF HAIR
Vellus hair Short, fine, downy, un-pigmented hair covering most of the body except the palms and soles; have no medulla or arrector pili; aid in evaporation of perspiration
2. Terminal hair - Long, think pigmented hair found on the scalp, legs, arms, and bodies of males and females. Coarser than vellus hair and, with the exception of gray hair, it is pigmented.

45. ANAGEN CATAGEN TELOGEN
HAIR GROWTH CYCLES
Anagen
Catagen
Telogen
Communication is certainly a very fashionable word, but it must be acknowledged that life, at least in the biological sense of the term, is above all a story of cellular communication. The life cycle of hair provides a remarkable illustration of this. Within every head of hair, each hair grows, falls and grows again, quite independently from its neighbor. Despite differences in speed of growth, all the hair in the world follows this timeless cycle which seems capable of reproducing itself many times over. However, very often this fine system of constantly regenerated life becomes seized up - so that little by little hair loss increase, the hair becomes rarer and finishes by disappearing altogether.
The average scalp hair growth of ½” per month will produce in excess of 250 ft. of hair a day if all the growth of the scalp was concentrated at one follicle!
There is no evidence to support the view that hair may be “fed” from the outside by application of “hair foods”. The external or visible hair is quite dead and so, despite it hungry condition, it is unable to accept or use this nourishment. The hungry condition is due to excess porosity – damage! For proper, healthy hair growth, hair relies on the constant supply of nourishment received by means of the blood and lymph systems and factors such as: health, diet, heredity, nerves, and age.
ANAGEN CATAGEN TELOGEN

46. Anagen phase Average growth about ½” per month.
90% of hair is growing at any given time.
Grows for a period of from two to six years.
Duration of hair life affected by gender, age, type of hair, heredity, nutrition, and health.
Scalp hair grows faster on women than men.
Grows faster between ages of and slows sharply after age 50.

47. The length of a person's hair depends on the length of the growing phase of the follicle. A person becomes bald if the scalp follicles become inactive and no longer produce new hair. Thick hair grows out of large follicles; narrow follicles produce thin hair.

48. Catagen phase Transition phase.
Ends the growth phase and lasts only one to two weeks.
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% of the scalp hair is in the catagen phase at any one time.

49. Telogen phase - Resting phase
Telogen phase - Resting phase. After catagen, the follicle begins a three to - six month phase of resting. About 10% of hair is in telogen phase at one time. After telogen, the cycle begins again. Entire growth cycle repeats itself every four to five years.

50. The hair growing Cuticle Oil film produced by sebaceous gland Hair
Hair bulb
Skin

51. Myth: Clipping, shaving, trimming, and cutting makes hair grow faster.
FACT: Have no effect on hair growth.
Myth: Scalp massage increases hair growth.
FACT: 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 FDA.
Myth: Gray hair is coarser and more resistant as pigmented hair.
FACT: Other than lack of pigment, gray hair is exactly the same than pigmented hair. It is not resistant because it is gray, and is not more resistant.

52. Myth: Amount of natural curl is determined by racial background.
FACT: Anyone of any race can have straight or extremely curly hair.
Myth: Hair with round cross-section is straight; hair with oval cross section is wavy and hair with flat cross section is curly.
FACT: Cross-sections of straight hair tend to be round and curlier and tends 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.

53. Hair Loss and Disorders

54. HAIR LOSS - Natural shedding of hair accounts for normal daily hair loss. Recent measurements indicate that the average rate of hair loss is closer to 35 to 40 hairs per day. Abnormal hair loss is called alopecia . The most common types are androgenic alopecia , alopecia areata , and postpartum alopecia . Over 63 million people in our country suffer from abnormal hair loss.

55. Emotional impact - how they are perceived by others: a recent study showed that compared to men who had hair, bald men were perceived as:
1. Less physically attractive (by both sexes)
2. Less assertive.
3. Less successful.
4. Less personably likable.
5. Older - by about five years.

56. HAIR LOSS IN MEN
1. Negative social and emotional effects.
2. More preoccupation with baldness.
3. Make effort to conceal or compensate for hair loss.

57. HAIR LOSS IN WOMEN
1. Devastating - Women try to hide it from everyone including their doctor.
2. Causes anxiety - Women feel helpless and less attractive; sometimes leads to suicide!

58. 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.
1. Affects 40 million men in U. S.
2. Affects 20 million women in U. S. Can begin as early as teens; frequently seen be age 40. By age 35, almost 40% of men and women show some degree of loss. Gene can be inherited from either side of family.

60. ALOPECIA AREATA - Sudden loss of hair in round or irregular patches; may occur on scalp or anywhere else on body. It’s highly unpredictable; affects almost 5 million people in the U. S.
1. Immune system attacks hair follicles.
2. Begins with one or more small, bald patches. Can progress to the total scalp hair loss (alopecia totalis ) or complete body hair loss (alopecia universalis ).
3. Occurs in males and females of all ages and races. Can begin in childhood.
4. Scalp shows no sign of inflammation.
5. No obvious signs of skin disorder or disease.

61. POSTPARTUM ALOPECIA - Temporary hair loss at conclusion of pregnancy
POSTPARTUM ALOPECIA - Temporary hair loss at conclusion of pregnancy. Growth cycle generally returns to normal within one year after the baby is delivered.

62. 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% regular and 5% extra strength; no known negative side effects.
Finasteride - Oral prescription for men only. Side effects include weight gain and loss of sexual function. Women who are pregnant or may become pregnant should not even touch a finasteride pill!

64. DISORDERS OF THE HAIR
Canities - Technical term for gray hair. Due to loss of natural pigment in hair.
Congenital canities - Exists at or before birth. Occurs in albinos mostly, occasionally in persons with normal hair.
Acquired canities - Due to old age; onset may occur prematurely in early adult life due to worry, anxiety, nervous strain, or prolonged illness.
Ringed Hair - Alternate bands of gray and dark hair.

65. HYPERTRICHOSIS - Also known as hirsuties or superfluous (unwanted) hair; characterized by the growth of terminal hair in areas of body that normally only grow vellus hair. Tweeze or remove by depilatories, electrolysis, shaving, or epilation.

66. TRICHOPTILOSIS - Split hair ends; Condition to lubricate and soften ends or cut.
TRICHORRHEXIS NODOSA - Knotted hair; a dry, brittle condition including formation of nodular swellings along the hair shaft. The hair breaks easily which creates a brush-like spreading of fibers along the hair shaft. Soften the hair with conditioners and moisturizers.

67. The cuticle has been damaged, so the twisted cortex “springs out”.
Split ends
The cuticle has been damaged, so the twisted cortex “springs out”.
A closer look at hair . . .

68. MONILETHRIX - Beaded hair; hair breaks between the beads or nodes
MONILETHRIX - Beaded hair; hair breaks between the beads or nodes. Condition hair and scalp.
FRAGILITAS CRINIUM - Brittle hair that causes splitting. Condition hair and scalp.

69. DISORDERS OF THE SCALP
Natural shedding of horny scalp scales that should not be mistaken for dandruff.
DANDRUFF – pityriasis ; small white scales that usually appear on the scalp and hair. Characterized by excessive proliferation, shedding and accumulation of surface cells.

70. Pityriasis capitis simplex - Dry type
Pityriasis capitis simplex - Dry type. Characterized by itchy scalp and small white scales attached to scalp or scattered loosely in the hair.
CAUSE: Sluggish scalp is caused by poor circulation, lack of nerve stimulation, improper diet, emotional and glandular disturbances, and poor personal hygiene.
TREATMENTS: Use of mild or mediated shampoos, scalp treatments, regular scalp massage, daily use of antiseptic scalp lotions, and mediated scalp ointments.

71. Pityriasis steatoides - Greasy or waxy type
Pityriasis steatoides - Greasy or waxy type. Scales become mixed with sebum, causing them to stick to scalp in patches; medical treatment is advisable.

72. Dandruff is a medical condition caused by an overgrowth of yeasts called Malassezia, normally found on the scalp. When an overgrowth occurs - often caused by stress, hormonal changes or even perspiration - the flakes associated with dandruffs appear.

73. VEGETABLE PARASITIC INFECTIONS
Tinea - The technical term for ringworm. Is caused
by vegetable parasites; and is highly contagious.
Begins with a 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 follicles; 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.

75. ANIMAL PARASITIC INFECTIONS
Scabies “itch mite” - Highly contagious, caused by itch mite; 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.
Lice Facts

76. Head Lice

77. Demodex folliculorum , or the demodicid, is a tiny mite, less than 0
Demodex folliculorum , or the demodicid, is a tiny mite, less than 0.4 mm long, that lives in your pores and hair follicles, usually on the nose, forehead, cheek, and chin, and often in the roots of your eyelashes. People with oily skin, or those who use cosmetics heavily and don't wash thoroughly, have the heaviest infestations ... but most adults carry a few demodicids. Inflammation and infection often result when large numbers of these mites congregate in a single follicle.
Demodex folliculorum

78. The mites live head-down in a follicle, feeding on secretions and dead skin debris. At the left, you can see three demodicids buried in the follicle of a hair, and you can also see the hair's shaft.
If too many mites have buried into the same follicle, it may cause the eyelash to fall out easily. An individual female may lay up to 25 eggs in a single follicle, and as the mites grow, they become tightly packed. When mature, the mites leave the follicle, mate, and find a new follicle in which to lay their eggs. The whole cycle takes between 14 to 18 days.

79. Sometimes demodex is called the 'face mite', since it is often associated with blackheads, acne and other skin disorders (although it is not the cause of these). Demodex are harmless and don't transmit diseases, but large numbers of demodex mites may cause itching and skin disorders, referred to as Demodicosis. The mites have tiny claws, and needlelike mouthparts for eating skin cells. Their bodies are layered with scales, which help them anchor themselves in the follicle. The mite's digestive system results in so little waste that the mite doesn't even have an excretory opening. So although there may be mites in your eyelashes, there isn't any mite poop! Thank goodness!

80. STAPHYLOCOCCI INFECTIONS
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.
About Staph

81. SUMMARY
We have learned that trichology enables the professional cosmetologist to better understand both the physical and microscopic properties of the hair. In order to give your clients the best possible services, you must be able to recognize those conditions of the hair and scalp needing treatment. Let’s review!

82. QUESTION: How does hair form and grow?
ANSWER: Living cells form in the follicle and mature through keratinization. As they form, they fill up with fibrous protein (keratin), move upward in the follicle, lose their nucleus and die. The hair shaft emerges from the scalp as a nonliving fiber composed of keratinized protein.
QUESTION: Name and describe the three layers of the hair.
ANSWER: -Cuticle: the outer most layer of hair, the protective covering.
-Cortex: the middle layer of the hair, a fibrous protein core formed by elongated cells, containing melanin pigment.
-Medulla: the innermost layer, referred to as the pith of the hair. Sometimes lacking in very fine and naturally blonde hair.

83. QUESTION: What are the differences between end bonds and side bonds?
ANSWER: End bonds or peptide bonds are the chemical bonds that join amino acids to each other. A long chain of amino acids linked by peptide bonds is called a polypeptide chain. These chains are cross-linked together by side bonds.
QUESTION: Describe the process of keratinization.
ANSWER: as newly formed cells in the hair mature, they fill up with keratin, move upward, lose their nucleus and die.

84. QUESTION: List and describe the two types of melanin responsible for natural hair color.
ANSWER: -eumelanin provides brown and black color to hair.
-pheomelanin provides natural hair colors from red and ginger to yellow/blonde tones.
QUESTION: What four factors about the hair should be considered in a hair evaluation?
ANSWER: Texture, porosity, elasticity and density.

85. QUESTION: What is the reason for normal daily hair loss?
QUESTION: List and describe the different types of hair and their locations on the body.
ANSWER: -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.
QUESTION: What is the reason for normal daily hair loss?
ANSWER: 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.

86. QUESTION: What are the factors that cause abnormal hair loss?
ANSWER: Genetics, age, hormonal changes, immune system
QUESTION: What are the only two approved hair loss treatments?
ANSWER: Minoxidil and Finasteride
QUESTION: List five hair disorders that can be treated in the salon.
ANSWER: Canities, ringed hair, hypertrichosis, trichoptilosis, trichorrhexis nodosa, monilethrix, fragilitas crinium

87. QUESTION: What is tinea?
QUESTION: Name the two main types of dandruff. Can either one be treated in the salon?
ANSWER: 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) and pityriasis steatoides (should be referred to a physician).
QUESTION: What is tinea?
ANSWER: Ringworm (small, reddened patches of little blisters).
QUESTION: Why are head lice so contagious?
ANSWER: They are transmitted from one person to another by contact with infested hats, combs, brushes and other personal articles.

88. Shaft
Root
A mature strand of human hair is divided into two parts: the hair root and the hair shaft. The hair root is the part located below the surface of the skin and the shaft is the portion that projects above the skin.
“My roots are showing again", "The roots are turning grey“ - everyday language is slightly misinformed, since the real hair roots can't be seen! Hair roots are protected in the depths of the Dermis , within the hair follicle , where the hair is generated and colored.
We have a very special relationship with our hair and are always surprised, even shocked, to learn that the part we see which goes to make up our precious head of hair is in fact, biologically dead. Furthermore, it receives no further assistance from the root which created it. However, the hair fiber does have an absolutely remarkable structure. Hair services are performed on the hair shafts – nothing we do penetrates or affects the root. The only thing that would affect the hair root would be an injury. If the papilla is destroyed, the hair will not grow again and if the follicle is damaged, the direction of hair growth could be affected.