Human Hair Flashcards
Hair care market: Retail value sales grow by ____% in current terms in 2022 to Php 49.6B
10
Hair care market: ________________________ is the best performing category in 2022, with retail value sales increasing by 42%
Salon professional hair care
Hair care market: ______________________ is the leading player with retail value share of 44%
Unilever Philippines Inc.
Hair care market: Largest category is ________________
standard shampoos
Hair care market: Sales of ________________ saw strong growth in retail volume terms
colorants
Hair care market: Availability of _______________ in sachets and tubs of 400-500 mL
conditioners
Hair care market: Strong focus on _______________ for product development and innovation
ingredients
Hair is a flexible thin _________ thread present on almost all surfaces of the human skin
keratin
Hair is not present on ______, soles of the feet, ________________ of the lips
palms; vermillion zone
T/F: Hair shaft is produced by rapidly multiplying matrix keratinocytes
True
T/F: Hair shaft is made up entirely of dead cells composed mainly of keratin which are held together by an extracellular cement-like substance
False. ……held together by an intercellular cement-like substance
Hair follicles are part of the _____________ unit
pilosebaceous
T/F: Sebum produced by sebaceous glands coats the hair and skin
True
Contraction of the _________________ attached to the hair follicle causes hair to stand up where it contracts
arrector pili muscle
Inner root sheath and outer sheath are called _______________
hair follicle
___________ is where blood vessels are. It supplies oxygen and nutrients for hair
Hair papilla
Actively growing cells are present in ____________. This is the source of new hair
Hair matrix
T/F: Shaving or cutting the hair cannot make it grow faster
True
This is the outermost structure of the hair. It protects the cortex, acts as a barrier, regulates the water content of the hair fiber, responsible for hair luster and texture
Cuticle
T/F: The cuticle is primarily composed of keratin
True
T/F: The cuticle is not usually the targeted part for formulations of conditioners
False. Cuticle is the targeted part of formulations
Major component of hair shaft. Contributes to mechanical properties of hair fiber like strength, elasticity, and curliness.
Cortex
T/F: The black color of the cortex is attributed to its melanin content, which is eumelanin.
True
T/F: The cortex is the targeted part if you want to color hair permanently, and permanently waving and straightening
True
The cortex contains cells rich in keratin filaments with amorphous matrix of _________ proteins
sulfur
T/F: Microstructure of the Human Hair Cortex
Cortical cells –> Macrofibrils –> 4 α-helix –> protofibrille –> microfibril
False. Cortical cells –> Macrofibrils –> microfibrils –> protofibrille –> 4 α-helix
_________ is also known as the core. It is composed of flattened cornified cells
Medulla
The medulla contains keratin framework supporting thin shells of amorphous material bonding _______________
air spaces
T/F: Thin hair is more resistant than thick hair
False
Enumerate the hair growth phases
Anagen, Catagen, and Telogen
Identify the hair growth phase
Nourishment of hair follicle via blood supply enables hair growth
Anagen
Identify the hair growth phase
Hair follicle detaches from nourishing blood supply. Similar to skin, hair cells are being pushed up, detaches from source and dies
Catagen
Identify the hair growth phase
This phase can last up to 2-6 years, in which the hair grows approximately 1 mm every 3 days
Anagen
Identify the hair growth phase
This is the end of the growth phase and melanin production is halted, also known as transition phase.
Catagen
Identify the hair growth phase
100-150 hairs are being removed per day, which is normal.
Telogen
Identify the hair growth phase
The duration of this phase is 2-3 weeks
Catagen
Identify the hair growth phase
Without nourishment, the hair dies and falls out.
Telogen
Identify the hair growth phase
This is also known as the resting phase
Telogen
Identify the hair growth phase
This is also known as the growth phase
Anagen
Identify the hair growth phase
This phase lasts for 2-3 months
Telogen
Identify the hair growth phase
85-90% of hairs undergo in this phase
Anagen
strong or weak bonds?
disulfide bonds, which are formed between sulfur atoms of cysteine
strong
strong or weak bonds?
hydrogen bonds (h-bonds)
weak
strong or weak bonds?
salt bonds (ionic bonds or coulomb interaction)
weak
strong or weak bonds?
can only be broken up chemically
strong
strong or weak bonds?
Allows hair to resume its original shape
strong
strong or weak bonds?
Contribute to shape, stability, and texture of hair
strong
strong or weak bonds?
Van der Waals force
weak
sino ang weak para sayo?
ako :>
are weak bonds that are easily broken by water and heat, and can alter hair’s overall shape. Most abundant
hydrogen bonds (h-bonds)
are weak bonds, and sensitive to pH and readily broken by alkaline or acidic conditions
salt bonds (ionic bonds or coulomb interaction)
are weak attractive forces between neutral molecules, and may be broken by water and heat
Van der Waals force
weak bonds that are formed between positive end of an amino acid and another negative end of an amino acid
salt bonds (ionic bonds or coloumb interaction)
T/F: Strong bonds are only broken when non-chemical treatments are applied
False. …. broken when chemical treatments are applied
T/F: weak bonds can be broken through combing and wetting the hair
True
T/F: Wet hair is less vulnerable than dry hair due to the protective properties of water
False. Wet hair is more vulnerable
Untreated hair comprises proteins that exhibit an isoelectric point near pH ______
3.7
Hair usually carries a _________ charge
negative
T/F: The middle part of the hair is the most negatively charged as it is exposed to stresses like combing, UV radiation, frequent use of shampoo
False. The tip of the hair is most negatively charged
T/F: Cationic ingredients are attracted to the hair more readily than anionics
True
Physical properties of human hair
- Durable and strong due to _______ in the cortex
- Elasticity related to the _______ of hair shaft
- _________ content causes cortex to swell and edges of the cuticle scales to lift
- High ___________________ and low ___________________ makes it easy to generate electrostatic charges by brushing & combing
Keratin
diameter
Water
electrical resistivity; dielectric constant
Human hair types are based on:
thickness, color, condition, shape, size, curliness, and greasiness
T/F: thin and coarse types of hairs are most fragile
False. Coarse types are more resistant to chemical processes, and thin hairs are most fragile and more susceptible to damage
The classifications of hairs based on thickness
coarse, medium, and thin
T/F: Medium hair is the standard thickness
True
Modified T/F: Natural hair color is the result of melanin in the cortex. Eumelanin is dark brown and black color to hair, and Pheomelanin provides red to blond notes.
BOTH TRUE
T/F: Healthy hairs are smooth and soft to the touch, and resistant to moisture. While damaged hairs are rough to the touch and dry
True
This type of hair, based on condition, have compact cuticle layer that is naturally resistant to moisture
Healthy hair
This type of hair, based on condition, have coarse texture; porous hair that absorbs liquid easily and tends to develop split ends
damaged hair
the ________ dictates the porosity; if the [answer] is more porous, the hair is able to absorb more moisture
cuticle
This type of hair (based on shape, size, and color) is mostly found on babies and formed in the first 5 months of their lives
Lanugo
This type of hair (based on shape, size, and color) is very fine, soft hair that covers the body of fetus; mostly shed at birth
Lanugo
This type of hair (based on shape, size, and color) is short, soft, colorless hair fibers commonly found on surfaces normally considered hairless; help in efficient evaporation and perspiration
Vellus hair (“down” or “fuzzy” hair)
This type of hair (based on shape, size, and color) is pigmented, thicker, found on scalp, chest, arms, legs, underarms and pubic hair
Terminal hair
This type of hair (based on shape, size, and color) have larger cross-sectional diameter, and are longer; found in different parts of the body. While eyelashes protect the eyes from dust
Terminal hair
This type of hair (based on shape, size, and color) is important in thermoregulation, perspiration and evaporation process
Vellus hair (“down” or “fuzzy” hair)
This type of hair (based on shape, size, and color) can function as protection from UV and cold insulation
Terminal hair
T/F: Vellus hairs can turn into terminal hairs upon reaching puberty. An example of this is the beard
True
T/F: Terminal hairs can turn into vellus hairs. An example of this is Male pattern baldness, a hair loss that happens when a type of androgen hormone called dihydrotestosterone (DHT) damages hair follicles.
True
Types of hairs based on curliness (shape of the hair shaft)
straight, wavy, curly, and kinky
African, Caucasian, and Asian
Types of hairs based on greasiness
dry hair and greasy hair
T/F: Dry hairs do not have enough moisture. This is because water is not retained
True
T/F: Dry hairs result from damaged (weathered) cuticle & cortex; dull, unhealthy appearance that is more visible in longer hair
True
T/F: Dryness is more visible in short hairs
False. Dryness is more visible in long hairs
T/F: In greasy hairs, overactive sebaceous glands is a contributory factor to development of dandruff
True
