Hydrogen peroxide volume indicates its oxidizing strength, with 40 volume (12%) being a high-lift agent used for significant lightening. It produces more deposit (color change) and high lift, suitable for dark hair to blonde, but risks damage if not controlled. Low deposit options imply weaker solutions (e.g., 10 or 20 volume), making 40 volume's high-lift capacity the defining characteristic in professional hair coloring.

Thio relaxers break disulfide bonds in hair to straighten it, which can lead to damage if the hair is porous or uneven. A conditioner filler, rich in proteins and moisturizers, coats the hair, evening out porosity and providing a protective base, enhancing relaxer uniformity and reducing breakage. Conditioning alone or even color application doesn't address porosity, while faster action or dye removal are unrelated to the process's preparatory needs.

Wash hands with soap and warm water removes chemicals, avoids skin irritation.

Correct: Option B - Red pigments.

Correct: Option A - Under cut is the correct technique.

The primary factor that controls how much hair is removed when shaping with a razor is the pressure applied. Greater pressure cuts more hair and produces a closer thin, while lighter pressure removes less. Direction, speed and how the razor is held influence the result but pressure is the main variable for controlling thinning intensity.

The primary structural component of hair, nails, and the outer skin layer (epidermis) is keratin, a tough, fibrous protein that provides strength and protection. Hemoglobin is a blood protein, melanin is a pigment, and calcium is a mineral, none of which form the bulk of these tissues. Keratin's cross-linked structure, rich in cysteine, enables its durability, making it essential for understanding skin and appendage biology in cosmetology.

Pull against hair growth direction is effective, less painful, removes hair from roots.

In razor tapering, removal per stroke is controlled by the blade angle relative to the hair shaft. A shallow angle removes little, a steeper angle removes more. Density, razor style, and texture influence technique choice but not the immediate amount removed by a single stroke.

Moisturizer soothes skin, reduces irritation, maintains moisture after lip waxing.

Correct: Option C - 18 hours – 24 hours is the standard period for a skin test.

Correct: Option B - Hair breakage is a common result of tight fastening.

Correct: Option b - Nucleus - The nucleus contains the genetic material necessary for cell reproduction.

In cosmetology, coarse hair can be thinned closest to the scalp because it has a thicker diameter and greater density, allowing stylists to remove bulk right near the roots without causing the hair to appear too sparse or damaged. Thinning shears or razors can be applied as close as 1/2 inch from the scalp on coarse hair to effectively reduce volume and prevent a bulky appearance, while blending seamlessly due to the hair's robust structure. In contrast, fine hair requires thinning farther from the scalp (typically 1-1.5 inches away) to avoid making it look limp, stringy, or overly thin, as its delicate strands do not blend as well when cut too close. Medium hair falls in between, often thinned about 1 inch away, and damaged hair should be approached cautiously regardless of texture to prevent further breakage. This principle is taught in cosmetology training to help stylists tailor cutting techniques to different hair types, ensuring optimal results for texture management, style longevity, and client satisfaction. Factors like hair porosity, elasticity, and overall health also influence how close thinning can be done, but texture is the primary determinant.

For achieving the best results in skip waving—a cosmetology technique that alternates finger waves with rows of pin curls or ridge curls to create a textured, undulating pattern with skipped sections for added dimension and movement—the most desirable hair length is 8 to 10 inches, providing sufficient length to form defined waves and curls without excessive bulk or difficulty in manipulation. Shorter lengths like 1 to 2 inches limit wave formation to basic textures, 3 to 5 inches allow minimal skips but lack depth, and 7 to 8 inches offer moderate results, but 8 to 10 inches enable full expression of the skip pattern, allowing curls to interlock with waves for a cohesive, voluminous style that brushes out smoothly. This length accommodates various hair types: straight hair benefits from the extra grip for holding waves, wavy hair enhances natural patterns, and curly hair can be relaxed slightly for control. Cosmetologists use products like setting lotion or mousse to enhance hold, sectioning the hair precisely to alternate waves and curls, often on the sides for a retro flair inspired by 1920s-1940s aesthetics. Factors such as scalp health, hair porosity, and client lifestyle influence adaptations, ensuring the style remains practical and flattering, with longer lengths facilitating easier brushing and longevity for events or daily wear.

Thinning with scissors is commonly called slithering. This technique uses scissors or thinning shears at a shallow angle to remove bulk and create softer lines. Clipper over comb is a clipper technique, razor cutting uses a straight razor for texture and edge, and layer cutting builds length differences rather than specifically thinning.

Correct: Option A - Shampooed

These methods are used to remove unwanted hair, often linked to conditions like hirsutism or hypertrichosis.

A keratoma also called a callus is a localized thickening of the stratum corneum produced by repeated friction or pressure. Chloasma is hyperpigmentation from hormonal influences lentigines are freckles and leucoderma is a loss of pigment. Only keratoma matches a thickened patch from friction.

The scientific study of hair, encompassing its growth patterns, structure, and associated disorders, is known as trichology, a specialized field that bridges dermatology and cosmetology. Trichology delves into the anatomy of the hair follicle, the cyclical growth phases - anagen (growth), catagen (transitional), and telogen (resting) - and conditions such as alopecia, dandruff, or excessive hair loss. This knowledge is invaluable for diagnosing scalp issues and tailoring hair care treatments, making it a cornerstone for professionals in hair restoration and salon services. Dermatology, while related, focuses more broadly on skin conditions including those affecting the scalp but is not specific to hair. Cosmetology involves the practical application of beauty techniques, including hair styling and coloring, but lacks the scientific depth of trichology. Biology, as a general science, covers all life forms and is too expansive to be specific to hair study alone.

Correct: Option B - 90%

The strand test involves stretching a hair strand to assess its elasticity.

Minimum pressure maintains curly hair structure, avoids temporary straightening.

Correct: Option D - Primary colors.

Trimmer is used to sharply edge hairlines around ears and neck, creating precise lines.

Damaged nails are prone to fungus due to weak structure, easy infection.

Taut skin reduces pain, increases accuracy when extending lashes, avoids skin damage.

Cuticle creams hydrate and protect, treating brittle and dry cuticles to prevent cracking. Removing dead cuticle is a physical process, not a cream's function, and encouraging nail growth or removing dry cuticle are beyond its scope. The emollient properties of creams, often with oils or urea, restore moisture, making this a primary use in nail care maintenance.

A smooth taper needs small progressive changes. The difference between neighboring lengths should stay within about half an inch to avoid steps or ridges. A quarter inch may be overly strict, while one inch or more creates visible demarcation.

Elasticity measures hair's ability to stretch and return to shape, a vital property in cosmetology for assessing hair health before chemical treatments. The strand test involves stretching a hair strand to evaluate elasticity, the allergy test checks for reactions, the push test assesses texture, and the pull test measures shedding. The strand test's focus on physical properties makes it the standard for elasticity assessment.

Moistening provides lubrication so the metal pusher glides without scratching the nail plate. This has nothing to do with circulation, the nail mantle, or visibility of the lunula.

Highlighting shampoo tints, also known as color-enhancing or toning shampoos, contain an aniline derivative tint combined with shampoo to deposit subtle color while cleansing, providing a gentle way to add highlights, neutralize unwanted tones, or refresh faded color without the commitment of permanent dyes. Aniline derivatives, synthetic organic compounds like para-phenylenediamine (PPD) or related amines, penetrate the cuticle slightly for semi-permanent effects, lasting 4-6 shampoos and ideal for blending grays or enhancing natural hues. This formulation allows for easy application during washing, with the shampoo base ensuring even distribution and conditioning benefits to counteract potential dryness. Unlike vegetable tints (natural extracts like chamomile for mild lightening), metallic and aniline mixes (which could cause incompatibilities), or compound dyes (multi-type blends), aniline-based highlighting shampoos offer predictable, vibrant results with low ammonia or peroxide levels. Cosmetologists recommend them for maintenance between full color services, considering hair porosity (porous hair absorbs more) and pH balance to avoid buildup. Historical development from early coal-tar dyes evolved to safer, regulated formulas, with patch tests mandatory to prevent allergies. This versatility makes them popular for at-home use, but professionals use them in salons for customized toning, such as purple shampoos for blondes to combat brassiness, ensuring enhanced shine and color longevity through proper lathering and rinsing techniques.

Coarse hair has thick cuticles, needs long time for chemicals to penetrate.

Correct: Option C - Henna.

Communicable disease spreads through direct or indirect contact, according to CDC.

Correct: Option d - Frenchman - Marcel Grateau, a French hairdresser, invented Marcel waving.

Correct: Option B - Treat the ends with a color filler.

In older cosmetology texts microbe refers mainly to bacteria which are single celled organisms. Each microorganism is one cell that reproduces by binary fission, so only one cell makes up a microbe.

Correct: Option D - Alopecia areata.

Aniline derivative tints cause eye irritation, not safe for eyebrows.

In galvanic electrotherapy the negative electrode induces an alkaline reaction at the skin surface while the positive electrode produces an acidic reaction. The positive pole acidifies the area and is therefore best described as producing an acidic reaction in contrast to the negative pole's alkaline effect.

Correct: Option D - Height

Nitrocellulose is the primary ingredient that gives nail polish its film-forming properties.

Correct: Option B - Diameter of the rollers has the most significant impact on curl tightness.

Blood-stained cloth is medical waste, needs double-bagging to prevent transmission.

Correct: Option c - Conditioner or cream rinses - These help detangle and smooth hair post-relaxing.

Hair removal methods address various dermatological conditions, each with specific indications. Hypertrichosis, excessive hair growth due to genetics or hormones, is effectively managed with waxing, shaving, electrolysis (permanent), and tweezing. Trichorrhexis nodosa involves hair shaft fragility, not excess growth. Pityriasis capitis simplex is dandruff, and androgenic alopecia is patterned hair loss, neither requiring removal techniques. The choice of method depends on hair type, skin sensitivity, and desired permanence, making this a practical application question.

Detailing at the neckline is most precise with point cutting using the tips of the scissors. This allows controlled removal and soft blending. Clippers can leave hard lines, thinning shears are for interior bulk removal, and full blade scissor cutting lacks edge precision.

Porous hair absorbs well, needs less chemicals for processing.

A chemical peel removes the outer skin layer, causing sensitivity and potential irritation. Waiting 3 to 5 days allows initial healing, while 3 to 5 weeks ensures full recovery from deeper peels, avoiding adverse reactions. After 12 weeks or 3 to 5 months is excessive, as facial treatments can resume once the skin stabilizes, guided by peel depth and client skin type, a critical safety measure in cosmetology.

To achieve uniform hair porosity and deposit a foundational base color before applying hair tint, a color filler is used first, as it evens out absorption rates by filling porous areas with pigment and conditioners, ensuring consistent color uptake and preventing patchy or off-tone results during the tinting process. This step is essential for damaged, bleached, or highlighted hair where high porosity leads to rapid color grab in ends versus slower in roots, often incorporating warm tones to counteract ashiness when darkening. Unlike a cream rinse (conditioner for detangling), color bleacher (lightener), or color shampoo (temporary deposit via wash), color fillers like those from Sally Beauty or professional lines involve mixing with developer, applying to dry hair, and processing 20-30 minutes before tinting. Factors such as hair type—curly hair often more porous—require customized shades, with strand tests verifying compatibility. Resources like Essence or Beautycon emphasize prepping with masks for low porosity to open cuticles or protein for high to seal, but fillers specifically bridge for tinting. This technique minimizes damage, enhances longevity, and is taught in color theory for safe, vibrant outcomes, advising clients on aftercare like moisture routines to maintain uniformity and avoid fading or brassiness over time.

Artificial hair tint removal requires a chemical that breaks down dye molecules without excessive damage. A dye solvent specifically targets synthetic colorants, while hydrogen peroxide or bleach powder with hydrogen peroxide lifts natural pigment, and a 40% H2O2 solution is too strong for safe use. The solvent's selective action preserves hair integrity, a critical consideration in color correction procedures.

Correct: Option B - Porosity.

A predisposition test for lash adhesive must be performed at least 24 hours before application to detect delayed hypersensitivity reactions. Waiting only minutes is insufficient to reveal a true allergic response.

Correct: Option d - Moist heat - Saturated steam provides moist heat, which is effective for sterilization by denaturing proteins.

When sectioning hair for a cold wave permanent, each section should be 1/2 inch shorter than the rod to ensure the hair fits neatly within the rod's length, allowing end papers to fold over without overhang, preventing fishhook ends, uneven curling, or solution drips, while promoting uniform wave patterns and reducing tension issues. This sizing—width slightly narrower than the rod (often 1/2 inch less)—facilitates secure wrapping, as the rod typically spans 2-4 inches, and sections match for density control based on hair thickness equaling the rod diameter. Unlike longer sections that cause bulging or slippage, or much shorter ones limiting curl size, this standard from Milady's guidelines optimizes chemical penetration in nine-section patterns (crown to nape), adapting for styles like bricklay or halo. Cosmetologists use combs for precise parting, considering scalp shape and desired volume—shorter sections for tighter curls—and test for elasticity pre-wrap. Historical cold waves, sans heat, rely on accurate sectioning for safety, minimizing breakage on fine hair or over-processing on coarse. This technique ensures long-lasting, bouncy results, with post-perm care like neutralizing and conditioning vital for bond reformation and client satisfaction in achieving desired textures from spirals to body waves.

Humectants, like glycerin or hyaluronic acid, attract and retain water, hydrating skin and hair, a vital property in moisturizers. Solvents dissolve substances, preservatives extend shelf life, and dissolving agent is less specific. Humectants' hygroscopic nature makes them essential in combating dryness in cosmetic products.

The process of removing excess dead cells from the skin surface is known as exfoliation, a technique that enhances skin texture, promotes cell renewal, and improves the absorption of subsequent skincare products. Exfoliation can be performed mechanically using tools like scrubs or microdermabrasion devices, which physically dislodge dead cells, or chemically with agents such as alpha hydroxy acids (AHA) or beta hydroxy acids (BHA) that dissolve the bonds holding dead cells together. This procedure reveals fresher, healthier skin underneath and is widely used in facial treatments to address dullness, clogged pores, or uneven tone. Cleansing removes surface dirt and oil but does not specifically target dead cell removal, moisturizing adds hydration without exfoliating, and toning adjusts skin pH without affecting dead cell layers, making exfoliation the distinct process here.

In hair bleaching, the developer (hydrogen peroxide) volume determines lift strength, with 40 volume (12%) being the highest safe concentration for professional use with bleach powder to achieve maximum lightening (e.g., black to pale blonde). Volumes like 20, 25, 30, or 35 are lower, used for less lift or gentler processes. Exceeding 40 volume risks severe hair damage, making it the ceiling in standard protocols.

Curly hair easily grows ingrown, causes folliculitis, boils.

Backcombing (teasing) creates volume at roots, increases fullness.

Cutting above 90° creates layers, increasing thickness and movement in hair.

Damaged hair breaks easily due to weak structure, cannot withstand chemicals.

Nitrile gloves resist chemicals, do not cause allergies, safe according to OSHA.

Cuticle oil maintains moisture, protects nails and surrounding skin.

Correct: Option C - Use the piggy back method of wrapping.

Test hot wax on technician's wrist checks temperature, avoids burning client.

UV lamp dries gel effectively, activates photochemicals in gel.

Cuticle nippers can be reused after proper disinfection.

Correct: Option d - Rectifier - This device converts AC to DC.

A substance capable of dissolving another to create a solution is defined as a solvent, a key concept in chemistry with significant applications in cosmetology. Solvents such as water, alcohol, or acetone work by interacting with solute molecules through forces like hydrogen bonding or polarity, breaking them apart to form a homogeneous mixture, as seen in nail polish removers or hair dye solutions. The solute, conversely, is the substance being dissolved, while a solution is the resulting mixture, and a binder serves to hold ingredients together rather than dissolve them. In cosmetic product development, solvents are essential for ensuring proper consistency, penetration, and efficacy, influencing the performance of creams, lotions, and other formulations.

Hair strength and elasticity—the ability to withstand tension, stretching, and environmental stressors while returning to its original shape—are primarily traceable to the cortex, the thick middle layer of the hair shaft composed of keratin proteins arranged in coiled bundles that provide structural integrity and flexibility. The cortex, making up 80-90% of the hair's mass, contains hydrogen, salt, and disulfide bonds that enable up to 30-50% stretch when wet and resilience when dry, influenced by genetics, nutrition, and care routines. In contrast, the medulla is an inner core often absent in fine hair and contributes minimally; the cuticle is the protective outer layer for shine and barrier function but not core strength; and the follicle is the root structure for growth, not shaft properties. Damage from heat, chemicals, or UV exposure weakens cortical bonds, leading to brittleness, while treatments like protein masks reinforce them. Understanding this anatomy allows cosmetologists to tailor services, such as recommending deep conditioning for low-elasticity hair or avoiding over-processing, ensuring healthy, vibrant styles that maintain form and resist breakage over time.

<p>Why Oil Is Used:</p><p>Oil acts as an insulator and barrier.</p><p>It prevents the alkaline solution (which can be caustic) from directly touching the skin.</p><p>It reduces irritation or chemical burns caused by the galvanic current or the alkaline product.</p><p>It also helps the electrode glide smoothly on the skin’s surface.</p><p>In other words:</p><p>When the anode (positive electrode) pulls the alkaline ions from the negative electrode through the skin, the current can dry or irritate the skin.</p><p>Applying oil before the procedure protects and conditions the skin barrier from that reaction.</p>

Correct: Option d - Decrease oil - This helps control oil production on the skin.

Neutralizer stops the chemical reducing action by re-oxidizing the broken disulfide bonds and reforming them into their new curled shape. It effectively 'rebonds' or 'locks in' the curl pattern established by the waving solution. Relaxing curled hair would undo the wave, and softening or closing the cuticle are secondary outcomes but not the main chemical purpose.

Clean skin with alcohol removes oil and dirt, increases wax adhesion.

The hair root's anatomy is foundational in cosmetology for hair growth and treatment planning. The bulb, a club-shaped structure at the base, houses the matrix where cell division occurs to generate hair. The shaft is the keratinized portion extending from the skin, the follicle is the surrounding sheath, and the papilla is a vascular structure supplying nutrients. Misidentifying these could lead to improper hair care techniques, making precise knowledge essential for professionals dealing with hair health and styling.

Bacteria are categorized by their morphology, which is critical for microbiological identification and treatment strategies. Cocci, being spherical, can form clusters (e.g., Staphylococcus) or chains (e.g., Streptococcus), with some causing infections like pneumonia or strep throat. Bacilli, with their rod-like structure, include beneficial species like Lactobacillus (used in yogurt fermentation) and pathogens like Escherichia coli (causing food poisoning). Spirilla, with their spiral shape, include harmless species like Spirillum volutans and pathogenic ones like Borrelia burgdorferi (Lyme disease). The question probes the general nature of these bacteria, which can range from symbiotic (aiding digestion) to pathogenic (causing disease), requiring a nuanced understanding of microbial ecology.

Brittle, cracked nails due to removers, aggressive filing or genetics weakening nails.

Anaphoresis uses the negative pole to drive alkaline solutions, soften tissue, and emulsify sebum. It helps desincrust congested follicles, making it most appropriate for acne prone and oily skin rather than dry or dehydrated skin.

Astringents are mildly acidic solutions typically pH 3 to 5 that cause tissue contraction and temporary pore tightening. Cassia oil and lavender are essential oils rather than acids and almond is a food containing fats and proteins. Therefore the item that has an acidic character is an astringent.

Holding and moving hair prevents scalp burns when using heat tools, ensuring safety.

Boils are caused by bacteria (staphylococcus aureus) causing inflammation, creating pus.

Proper handwashing time is at least 20 seconds to remove dirt, oils, and most transient microorganisms effectively. This is a standard hygiene guideline in both cosmetology and healthcare settings to maintain sanitation. Less time may not adequately break down and rinse away contaminants.

Correct: Option B - Closing the scissors & facing the cosmetologist.

Correct: Option D - Brittle

Wrapping from one side to other at nail tip ensures durability and aesthetics.

Correct: Option B - Lighten the hair

Covered containers prevent contamination and evaporation, essential for all cosmetics (creams, liquids, lotions) to maintain efficacy and safety. Storing only creams or liquids excludes other forms, while all cosmetics encompasses the broadest category, aligning with hygiene standards in professional settings.

Correct: Option B - Achieves yellow color.

A thorough rinse for at least three minutes removes residual waving solution and dilutes remaining chemicals, preventing continued reducing action. It also helps reintroduce oxygen and prepares the hair structure so the neutralizer can rebond disulfide links effectively, resulting in a safer, more predictable neutralization and better hair integrity.

70% alcohol cleans oil and dirt, increases gel polish adhesion.

Correct: Option B - A razors.

Correct: Option B - All cosmetics.

Correct: Option B - The lighten over lap to bleached hair.

Uniform layer creates consistent length, increases even thickness.

Aniline derivative tints, including para-phenylene-diamine (PPD), a key oxidative agent used in permanent hair colors for its ability to penetrate the cortex and form large color molecules with hydrogen peroxide, are also referred to as synthetic organic tints, distinguishing them from natural or inorganic alternatives due to their chemically synthesized aromatic amine structure derived from aniline. These tints offer long-lasting, vibrant shades with excellent gray coverage but require patch tests for allergies, as PPD can cause reactions in sensitive individuals. Unlike vegetable tints from plant extracts like henna for temporary hues; metallic dyes with metal salts for progressive coloring; or compound dyes mixing types; synthetic organic tints dominate modern color lines for their versatility in lifting and depositing color. Cosmetologists must follow manufacturer guidelines, considering hair porosity and previous treatments to avoid damage, while regulations like EU limits on PPD concentrations ensure safety. This classification underscores their role in professional salons for customizable, durable results that evolve with trends in fashion and personal expression.

The average lifespan of hair on the human scalp is approximately 4-7 years.

Masks often include ingredients to detoxify and stimulate. Fuller earth (clay) absorbs oil and removes dead cells while stimulating circulation, zinc oxide soothes but lacks drawing action, and chamomile calms without significant absorption. The clay's adsorbent properties and mild exfoliation make it ideal for oily skin treatments in cosmetology.

Waving lotion that runs toward the scalp can be accelerated by body heat and cause overprocessing or irritation. Applying the lotion a safer distance from the scalp, typically between one half inch and one inch, reduces runoff and direct thermal acceleration at the scalp while still allowing the lotion to act on the hair shaft.