I85PREP
⌘ K
MD Cosmetology study materials
MD Cosmetology study resources

MD Cosmetology practice questions

One question at a time. Build your MD Cosmetology understanding.

First 50 of 200 questions. Each one lists the choices, the correct answer, and an explanation. The checker at the top of this page saves progress in this browser when it is available.

Continue in the practice tool above to load more questions, 50 at a time.

Question 1Hair Care and Hairdressing

In a virgin hair colour service, which layer must the colour molecules penetrate to produce a lasting change?

  1. The cuticle, then the cortex Correct answer.
  2. The medulla only
  3. The sebaceous gland
  4. The follicle bulb

Explanation

Permanent colour must pass through the protective cuticle and deposit pigment within the cortex, where the new colour is locked in. The medulla is a central core that plays little role in colour deposition.

Question 2Hair Care and Hairdressing

A client's hair has a pH of about 4.5. How is this best described?

  1. Strongly alkaline and buffered
  2. Acidic Correct answer.
  3. Neutral
  4. Strongly alkaline

Explanation

Hair and scalp naturally sit on the acidic side of the pH scale, around pH 4.5 to 5.5. Values below 7 are acidic, and this acidity helps keep the cuticle compact and smooth.

Question 3Hair Care and Hairdressing

Which hair texture is generally the most resistant to chemical penetration?

  1. Fine hair
  2. Medium hair
  3. Vellus hair
  4. Coarse hair Correct answer.

Explanation

Coarse hair has a wider shaft and a tightly overlapping, thicker cuticle, so chemicals take longer to penetrate. Fine hair, by contrast, processes quickly because its cuticle is thinner and less dense.

Question 4Hair Care and Hairdressing

What is the primary purpose of a patch test before applying an oxidative hair colour?

  1. To test the developer strength
  2. To detect a possible allergic reaction Correct answer.
  3. To measure processing time
  4. To check colour accuracy

Explanation

A patch test screens for an allergic sensitivity to ingredients such as oxidative dyes, so a reaction appears on a small area rather than the whole head. It does not predict the final shade or the processing time.

Question 5Hair Care and Hairdressing

Which tool is designed to thin and texturise hair while removing bulk?

  1. Wide-tooth comb
  2. Tail comb
  3. Blow dryer
  4. Razor Correct answer.

Explanation

A razor slices through hair at an angle, creating soft, tapered ends and removing bulk, which makes it useful for thinning and texturising. The other tools listed do not cut or thin hair at all.

Question 6Hair Care and Hairdressing

What does the term 'hair density' describe?

  1. The number of strands per square centimetre of scalp Correct answer.
  2. The oiliness of the scalp
  3. The diameter of an individual strand
  4. The amount of curl in the hair

Explanation

Density refers to how many hairs grow per unit area of scalp, which determines how full or sparse the hair looks. Strand diameter is texture, not density.

Question 7Hair Care and Hairdressing

Which shampoo type is best suited to a client with an oily scalp and limp hair?

  1. A balancing or clarifying shampoo Correct answer.
  2. A protein-repair mask
  3. A leave-in silicone serum
  4. A heavy moisturising cream shampoo

Explanation

Balancing or clarifying shampoos gently remove excess sebum and product build-up, which helps limp hair look fresher and fuller. Heavy creams and serums add weight and can worsen limpness.

Question 8Hair Care and Hairdressing

In permanent waving, what is the role of the reducing agent?

  1. It neutralises the waving lotion
  2. It raises the cuticle pH to 10
  3. It breaks disulfide bonds in the cortex Correct answer.
  4. It rebuilds disulfide bonds

Explanation

The reducing agent in a perm lotion breaks disulfide bonds in the cortex, allowing the hair to be reshaped around the rods. The neutraliser then rebuilds those bonds in the new position.

Question 9Hair Care and Hairdressing

A client with previously bleached hair wants a level 6 permanent colour. Which approach is safest?

  1. Apply the colour at full strength for the full time
  2. Apply a high-lift tint mixed with 40-volume developer
  3. Skip the strand test to save time
  4. Use a lower-volume developer and perform a strand test first Correct answer.

Explanation

Bleached hair is porous and absorbs dye quickly, so a gentler developer and a strand test reduce the risk of over-processing and uneven results. A strand test shows how the compromised hair will respond before the full application.

Question 10Hair Care and Hairdressing

What is the purpose of backcombing when building a chignon or updo?

  1. To add volume and support at the crown Correct answer.
  2. To remove product residue
  3. To speed up drying
  4. To smooth the cuticle

Explanation

Backcombing creates a dense cushion of hair that supports the shape of an updo and adds volume. It is a structural technique, not a smoothing or cleansing step.

Question 11Hair Care and Hairdressing

When blow-drying a fine, straight bob for a smooth finish, which technique is most appropriate?

  1. Point the nozzle downward and follow the hair with a round brush Correct answer.
  2. Apply a heavy wax before drying
  3. Point the nozzle upward to lift the roots only
  4. Use a diffuser on high heat with the hair scrunched

Explanation

Directing the airflow downward with the cuticle closes the cuticle and produces a smooth, shiny finish. A round brush gives tension and shape while the nozzle follows the hair.

Question 12Hair Care and Hairdressing

Which result indicates that a relaxer has been left on too long?

  1. Straightening beyond the desired level with scalp irritation Correct answer.
  2. Even, controlled smoothing
  3. Slight loosening of the curl
  4. Excessive curl retention

Explanation

Over-processing with a relaxer straightens the hair more than intended and often causes scalp burning or irritation. The target is controlled smoothing, not total straightening on the first pass.

Question 13Hair Care and Hairdressing

What is the main function of a conditioner's cationic surfactants?

  1. To lighten the hair
  2. To increase curl
  3. To cleanse the scalp
  4. To bond to negatively charged hair and reduce static and friction Correct answer.

Explanation

Cationic surfactants carry a positive charge and bind to the negatively charged hair surface, smoothing the cuticle and reducing static and friction. This makes hair easier to comb and feel softer.

Question 14Hair Care and Hairdressing

A client's colour fades quickly after each service. Which factor most likely explains this?

  1. The hair is very short
  2. The hair is naturally straight
  3. The client uses a wide-tooth comb
  4. The cuticle is very porous and loses pigment readily Correct answer.

Explanation

Porous hair has a raised, open cuticle, so dye molecules leach out faster with washing and heat styling. Porosity is the main driver of rapid colour loss, not length or comb type.

Question 15Hair Care and Hairdressing

Which sectioning pattern is used to create a uniform blunt fringe?

  1. Horizontal sections with zero elevation Correct answer.
  2. Radial sections
  3. Diagonal sections
  4. Vertical sections with 90-degree elevation

Explanation

Horizontal sections cut with zero elevation produce a straight, uniform line, which is the basis of a blunt fringe. Elevation would create graduation or layering instead of a solid edge.

Question 16Hair Care and Hairdressing

What is a strand test primarily used to determine before a colour service?

  1. The correct shampoo to use afterwards
  2. The client's preferred style
  3. The client's scalp type
  4. How the hair will respond to the colour formula and timing Correct answer.

Explanation

A strand test shows how the hair reacts to the chosen formula, developer and timing, allowing the stylist to adjust before the full application. It is a predictive tool for the chemical result.

Question 17Hair Care and Hairdressing

Which factor increases the risk of scalp irritation during a bleach service?

  1. Applying barrier cream around the hairline
  2. Leaving the lightener on the scalp for too long Correct answer.
  3. Using a lower-volume developer
  4. Sectioning the hair thinly

Explanation

Prolonged contact between lightener and the scalp increases irritation and burning, especially at higher developer strengths. Barrier cream and correct timing help reduce this risk.

Question 18Hair Care and Hairdressing

A client with a sensitive scalp requests a service using a product with a high pH. What is the most appropriate action?

  1. Proceed with the full service without changes
  2. Apply the product to the whole head at once
  3. Perform a patch test and consider a lower-pH alternative Correct answer.
  4. Increase the developer strength to speed up the process

Explanation

High-pH products are more likely to irritate a sensitive scalp, so a patch test and a gentler, lower-pH alternative are the safer choices. Increasing strength or applying to the whole head raises the risk further.

Question 19Hair Care and Hairdressing

Which ingredient is commonly used as the oxidising agent in hair colour developers?

  1. Sodium hydroxide
  2. Hydrogen peroxide Correct answer.
  3. Cetyl alcohol
  4. Ammonium thioglycolate

Explanation

Hydrogen peroxide is the standard oxidising agent in developers; it lifts the cuticle and drives the colour reaction. Thioglycolate is a reducing agent used in perms and sodium hydroxide is a relaxer ingredient.

Question 20Hair Care and Hairdressing

What is the main advantage of a lower-volume developer when the target lift is small?

  1. It gives more control and less damage Correct answer.
  2. It removes the need for a strand test
  3. It permanently straightens the hair
  4. It produces more lift than a high-volume developer

Explanation

A lower-volume developer releases less oxygen, giving slower, more controlled processing with less stress on the hair. It is chosen when only a small amount of lift is needed.

Question 21Hair Care and Hairdressing

A client's hair is described as having high elasticity. What does this indicate?

  1. The hair breaks easily when stretched
  2. The hair stretches and returns to its original length without breaking Correct answer.
  3. The hair has been over-bleached
  4. The hair is very dry and brittle

Explanation

High elasticity means the hair can stretch and spring back without snapping, which indicates good internal strength. Low elasticity, by contrast, means the hair snaps quickly and signals damage.

Question 22Hair Care and Hairdressing

In a colour correction, why is it important to assess the hair's porosity before applying a pre-lightener?

  1. Porosity has no effect on lightening
  2. Porous hair cannot be lightened at all
  3. Porous areas process faster and can over-lighten Correct answer.
  4. Porosity determines the client's preferred shade

Explanation

Porous regions absorb and release lightener faster, so they can over-process while denser areas are still lifting. Mapping porosity allows the stylist to apply product strategically and monitor timing.

Question 23Hair Care and Hairdressing

Why does hair feel rougher after an alkaline chemical service, and what restores smoothness?

  1. The medulla swells; heat styling restores smoothness
  2. The cuticle lifts; an acidic finishing product helps close it Correct answer.
  3. The follicle closes; shampoo restores smoothness
  4. The cortex dissolves; only cutting restores smoothness

Explanation

Alkaline products raise the cuticle scales, increasing friction and roughness. Acidic finishing products lower the pH and help the cuticle lie flat again, restoring smoothness and shine.

Question 24Hair Care and Hairdressing

A client with a round face wants a cut that creates length and slims the face. Which choice best supports this?

  1. A blunt chin-length bob with a straight fringe
  2. A centre-parted style with volume at the sides
  3. A short, wide pixie cut
  4. Long layers with face-framing pieces below the jaw Correct answer.

Explanation

Long layers with face-framing pieces below the jaw draw the eye downward and create vertical lines, which visually lengthens a round face. Styles that add width at the cheeks or jaw work against this goal.

Question 25Hair Care and Hairdressing

Why is a neutraliser essential after a permanent wave?

  1. It rebuilds the disulfide bonds in their new shape Correct answer.
  2. It adds colour to the hair
  3. It removes the waving lotion from the hair
  4. It closes the follicle

Explanation

After the reducing agent breaks disulfide bonds, the neutraliser reforms them in the new curled position, locking the wave in place. Without it, the wave would relax back and the hair would remain fragile.

Question 26Hair Care and Hairdressing

Which term describes the direction in which a client's hair strands naturally fall from the scalp?

  1. Hair texture
  2. Hair porosity
  3. Hair density
  4. Hair growth pattern Correct answer.

Explanation

Hair growth pattern (also called hair stream or fall) describes the natural direction in which strands grow and lie against the scalp, and it dictates how a cut will sit and where parting lines will fall. It is assessed before cutting because cowlicks and whorls at the hairline or crown change how lengths behave.

Question 27Hair Care and Hairdressing

A client with coarse, curly hair books a blow-dry for a smooth finish. Which preparation step best supports a lasting smooth result?

  1. Rough-dry to 80 percent before sectioning Correct answer.
  2. Comb through soaking wet hair with a wide-tooth comb
  3. Apply a light serum to dry ends only
  4. Apply heavy wax to the mid-lengths before drying

Explanation

Removing excess moisture with rough-drying before sectioning lets tension and heat do the smoothing work rather than evaporating surface water, which shortens drying time and reduces frizz. Curly, coarse hair holds a great deal of water, so pre-drying is especially important for control.

Question 28Hair Care and Hairdressing

Which property of the hair shaft is measured by pulling a wet strand and observing how far it stretches before breaking?

  1. Texture
  2. Elasticity Correct answer.
  3. Porosity
  4. Density

Explanation

Elasticity is the hair's ability to stretch and return to its original length without breaking, and it is tested on damp hair because water disrupts hydrogen bonds and reveals the true strength of the cortex. Good elasticity indicates a sound cortex that can withstand chemical services.

Question 29Hair Care and Hairdressing

During a colour consultation, which observation most strongly suggests the hair has high porosity?

  1. Strands stretch far and spring back firmly
  2. Wet hair dries very slowly after shampooing
  3. Colour absorbs quickly but fades rapidly Correct answer.
  4. Strands feel smooth and the cuticle reflects light evenly

Explanation

High porosity means the cuticle layer is raised or damaged, so pigment and moisture enter quickly but also leave quickly, producing fast uptake in the salon and rapid fading afterwards. This pattern calls for gentler processing and a filling or pre-treatment step.

Question 30Hair Care and Hairdressing

Which tool is designed to thin bulk from a section while leaving the outline length intact?

  1. Straight razor
  2. Blunt cutting shears
  3. Wide-tooth comb
  4. Thinning shears Correct answer.

Explanation

Thinning shears have a comb-like blade that removes a proportion of strands within a section, reducing weight and creating movement without shortening the outer line. They are used sparingly on fine hair because overuse removes too much volume.

Question 31Hair Care and Hairdressing

A client requests a graduated bob with volume at the back. Which cutting approach builds that shape?

  1. Cutting each back section longer at the top and shorter at the nape Correct answer.
  2. Cutting all sections to one horizontal guideline
  3. Cutting vertical sections with no elevation throughout
  4. Cutting the perimeter first and point-cutting the crown

Explanation

Graduation stacks length so that lower sections are shorter and upper sections are longer, creating weight and volume at the back of the head. Cutting to a single guideline or with no elevation produces a solid or one-length form instead.

Question 32Hair Care and Hairdressing

Which developer strength is normally selected for a deposit-only tint that needs no lift?

  1. 3 percent (10 volume) Correct answer.
  2. 12 percent (40 volume)
  3. 6 percent (20 volume)
  4. 9 percent (30 volume)

Explanation

A deposit-only tint needs enough developer to activate the dye but not enough to lighten the natural pigment, and 10 volume delivers that minimal lift. Higher strengths add lightening and are chosen only when the target shade requires it.

Question 33Hair Care and Hairdressing

Why is a patch test recommended before applying a permanent oxidative colour to a new client?

  1. To identify a possible allergic reaction to the dye ingredients Correct answer.
  2. To check the hair's elasticity before processing
  3. To predict whether the final shade will suit the client's skin tone
  4. To confirm how long the colour will last between services

Explanation

A patch test exposes a small area of skin to the colour formula to detect sensitisation before the full service, protecting the client from a reaction during processing. It is a safety check and does not predict shade suitability or longevity.

Question 34Hair Care and Hairdressing

A client's mid-lengths and ends process much faster than the regrowth during a tint application. Which application strategy manages this best?

  1. Apply to the mid-lengths first and the regrowth last
  2. Apply a stronger developer to the mid-lengths and ends
  3. Apply the whole head at once and rinse early
  4. Apply to the regrowth first and the mid-lengths and ends near the end of processing Correct answer.

Explanation

Porous mid-lengths and ends take colour quickly, so applying the regrowth first gives the resistant new growth its full processing time while the faster-absorbing lengths receive less exposure. This evens out the final result and reduces over-deposit on the ends.

Question 35Hair Care and Hairdressing

Which action best protects the scalp when applying a lightener close to the hairline?

  1. Apply the product directly onto the scalp to speed processing
  2. Use a higher-volume developer to shorten the contact time
  3. Leave a thin band of untreated hair at the hairline
  4. Apply a barrier cream and keep the product off the skin Correct answer.

Explanation

A barrier cream plus careful placement keeps lightener off the skin, reducing the risk of chemical irritation and burns while still allowing the hairline to be lifted. Lightener should never be worked into the scalp, and raising developer strength increases both irritation and damage.

Question 36Hair Care and Hairdressing

What is the purpose of sectioning hair into four quadrants before a precision cut?

  1. To divide the head into manageable working areas for consistent control Correct answer.
  2. To determine the client's natural growth pattern
  3. To reduce the amount of hair that needs cutting
  4. To make the hair easier to shampoo

Explanation

Quadrant sectioning divides the head into equal, manageable areas so each subsection can be cut with consistent tension, elevation and reference to the same guidelines. It is a control technique and does not itself diagnose growth patterns or alter the amount cut.

Question 37Hair Care and Hairdressing

A client with a long face shape wants a cut that reduces apparent length. Which design choice supports this?

  1. A long, one-length cut past the shoulders
  2. A fringe with width across the forehead Correct answer.
  3. Vertical layers framing the jaw only
  4. A centre parting with no fringe

Explanation

A fringe creates a horizontal line across the forehead that visually shortens the face and balances its length. Centre partings and long one-length shapes draw the eye downward and emphasise length instead.

Question 38Hair Care and Hairdressing

Which characteristic most clearly distinguishes a hard press from a soft press when straightening textured hair with a thermal comb?

  1. The direction in which the comb is held
  2. The type of shampoo used beforehand
  3. The number of passes and the resulting degree of straightening Correct answer.
  4. The temperature of the pressing comb

Explanation

A hard press uses more passes and higher tension to straighten the hair almost completely, while a soft press leaves some of the natural wave or bulk. The distinction lies in the degree of straightening achieved through passes, not in shampoo choice or comb orientation.

Question 39Hair Care and Hairdressing

Which aftercare advice best supports hair that has just received an oxidative colour service?

  1. Apply a heavy oil treatment immediately after rinsing
  2. Wash daily with a clarifying shampoo to keep the colour bright
  3. Re-colour the whole head within a week to seal the shade
  4. Wait several days before shampooing and use a colour-protecting shampoo Correct answer.

Explanation

Freshly oxidised colour continues to settle in the cortex, and waiting before the first shampoo plus using a gentle, colour-protecting cleanser slows fading. Clarifying shampoos strip pigment, and immediate heavy oil or repeat colouring is unnecessary and can stress the hair.

Question 40Hair Care and Hairdressing

A client's hair is very fine and lacks volume at the crown. Which combination of cut and styling choices best creates lasting lift?

  1. A blunt fringe with a strong-hold wax applied at the crown
  2. Short, layered graduation at the crown with light styling product at the roots Correct answer.
  3. Long, one-length layers with a smoothing serum throughout
  4. A blunt one-length cut with heavy styling cream at the roots

Explanation

Layering and graduation remove weight so shorter strands can support lift, and a light product at the root adds hold without dragging the hair down. Heavy products and long one-length shapes weigh fine hair flat.

Question 41Esthetics and Skin Care

Which skin layer contains the Langerhans cells that serve as the immune sentinels of the epidermis?

  1. Stratum lucidum
  2. Stratum basale
  3. Stratum corneum
  4. Stratum spinosum Correct answer.

Explanation

Langerhans cells reside mainly in the stratum spinosum, where they capture antigens and present them to T lymphocytes. They are not produced in the cornified layer or the thin lucidum layer. Melanocytes occupy the basale, but their role is pigment transfer rather than immune surveillance.

Question 42Esthetics and Skin Care

A client with oily skin and visible shine asks which product consistency best suits daily moisturizing. Which formulation is most appropriate?

  1. A water-based gel Correct answer.
  2. An oil-based serum
  3. A rich occlusive balm
  4. A heavy cream with lanolin

Explanation

Oily skin benefits from lightweight, water-based gels that hydrate without adding heavy lipids that increase shine and congestion. Rich balms, lanolin creams, and oil serums are more occlusive and better suited to dry or mature skin. Matching vehicle to skin type keeps the barrier comfortable while controlling greasiness.

Question 43Esthetics and Skin Care

Which ingredient is a beta hydroxy acid commonly used in salon peels for its lipophilic, pore-penetrating action?

  1. Glycolic acid
  2. Hyaluronic acid
  3. Salicylic acid Correct answer.
  4. Lactic acid

Explanation

Salicylic acid is a beta hydroxy acid that is lipid soluble, allowing it to penetrate sebaceous follicles and help exfoliate within pores. Glycolic and lactic acids are alpha hydroxy acids that act mainly at the skin surface. Hyaluronic acid is a humectant, not an exfoliant.

Question 44Esthetics and Skin Care

What is the primary function of the acid mantle on the skin surface?

  1. To promote desquamation of the nail plate
  2. To maintain a slightly acidic pH that supports barrier function Correct answer.
  3. To accelerate melanin synthesis
  4. To increase sebum viscosity

Explanation

The acid mantle is a slightly acidic film of sebum and sweat that supports the barrier, limits pathogenic bacteria, and favors normal enzyme activity. It does not drive melanin production or alter sebum viscosity. Nail desquamation is unrelated to the skin's surface film.

Question 45Esthetics and Skin Care

During a facial, at which point should extractions of comedones generally be performed?

  1. Before any makeup removal
  2. After cleansing and softening the skin with steam Correct answer.
  3. Before cleansing the skin
  4. Immediately after applying the finishing moisturizer

Explanation

Extractions are performed after cleansing and warming the skin, since steam and softened keratin make comedones easier to express with less trauma. Extracting before cleansing risks pushing surface debris and bacteria into follicles. The finishing moisturizer is applied after extractions to soothe the skin.

Question 46Esthetics and Skin Care

Which type of skin lesion is a flat area of color change, such as a freckle, that is neither raised nor depressed?

  1. Papule
  2. Pustule
  3. Macule Correct answer.
  4. Nodule

Explanation

A macule is a flat, circumscribed change in skin color without elevation or depression, as seen in freckles. Papules and nodules are raised solid lesions of differing depth, and pustules contain pus. Recognizing lesion type guides whether a service is safe to perform.

Question 47Esthetics and Skin Care

Which muscle is responsible for the horizontal forehead wrinkles that a cosmetic treatment may target?

  1. Platysma
  2. Frontalis Correct answer.
  3. Masseter
  4. Orbicularis oculi

Explanation

The frontalis muscle elevates the brows and creates horizontal forehead lines when it contracts. The orbicularis oculi closes the eyelids and produces crow's feet, while the masseter affects the jaw and the platysma affects the neck. Identifying the correct muscle is essential for planning targeted treatments.

Question 48Esthetics and Skin Care

Which Fitzpatrick skin type is described as always burning and never tanning, with very pale skin and light eyes?

  1. Type IV
  2. Type I Correct answer.
  3. Type V
  4. Type III

Explanation

Fitzpatrick type I skin is very fair, burns easily, and never develops a tan, reflecting minimal melanin protection. Types III and IV tan more readily, and type V is brown skin that rarely burns. Correct typing guides peel selection and UV counseling.

Question 49Esthetics and Skin Care

A client using a prescription retinoid reports stinging after a glycolic acid facial. Which approach best reflects sound practice?

  1. Defer the peel and review the client's retinoid schedule Correct answer.
  2. Apply a strong astringent to reduce the sting
  3. Increase the acid concentration to speed results
  4. Proceed with the same protocol and add a scrub

Explanation

Prescription retinoids thin the stratum corneum and increase sensitivity, so combining them with strong acids raises the risk of irritation and barrier damage. The safe response is to defer the exfoliating peel and discuss timing with the client and their prescriber. Increasing concentration or adding mechanical scrub compounds the risk.

Question 50Esthetics and Skin Care

Which statement correctly distinguishes a comedogenic product from a non-comedogenic one?

  1. Non-comedogenic products cannot cause irritation
  2. Non-comedogenic products always contain salicylic acid
  3. Comedogenic products are fragrance free
  4. Comedogenic products tend to clog pores Correct answer.

Explanation

Comedogenic refers to a product's tendency to promote comedone formation by occluding follicles, whereas non-comedogenic products are formulated to minimize that risk. The label says nothing about fragrance content or guaranteed active ingredients. Non-comedogenic products can still irritate sensitive skin.