Lecture 1 - Intro: The Skin, Skin Care Products, and Raw Materials

Question 1

What is purpose of skin and hair?

Answer 1

Protection, keep in water

Question 2

Skin is the largest organ. What are the basic stats?

Answer 2

Approx 8 pounds and 22 square feet

Question 3

Define the epiderms

Answer 3

• biweekly renewal by maturation and exfoliation

- fed from the dermis and subcutaneous circulation

Question 4

Define the dermis

Answer 4

actively metabolizing tissue retains structure (contains elastic fibers)

Question 5

Define hair follicle

Answer 5

• origin of hair fibers

- epidermal tissue seated in dermis

Question 6

function of epidermal cells

Answer 6

continually replicating and maturing into the cornified protective stratum corneum layer

Question 7

function of dermal fibroblast cells

Answer 7

responsible for production and homeostasis of the underlying structural layer of skin by synthesis and excretion of fibrillar proteins- collagens and elastin and mucopolysaccharides (hyaluronic acid, dermatin)

Question 8

function of melanocytes

Answer 8

production and transport of melanin granules inter- and intracellularly

Question 9

function of langerhans cells

Answer 9

dendritic immunologic actors

Question 10

function of hair follicle

Answer 10

produces complex hair structure in an orderly cycle from epidermal cells

Question 11

function of sebaceous gland

Answer 11

holocrine excretory gland producing sebum for hair and skin lubrication exiting into hair shaft

Question 12

function of eccrine sweat glands

Answer 12

secretory bodies that act to control internal temperature by secreting water while maintaining electrolyte balance

Question 13

function of apocrine sweat glands

Answer 13

• associated with hair follicles secretes milky fluid- proteins and lipids
• may have pheromonal function, impacts body odor

Question 14

function of nerve receptors

Answer 14

tactile, temperature, pressure stimulus response

Question 15

function of Merkel’s Disk

Answer 15

touch, pressure (static)

Question 16

Function of Meissner’s corpuscle

Answer 16

touch, pressure (dynamic)

Question 17

Function of Ruffini ending

Answer 17

stretching of skin, pressure sensor

Question 18

Function of Pacinian corpuscle

Answer 18

Deep pressure, vibration (dynamic)

Question 19

function of Krause end bulb

Answer 19

Thermoreceptor

Question 20

Free nerve endings

Answer 20

not differentiated, more simple receptors for pain/heat/cold

Question 21

Why does tan only last a few weeks and tattoo lasts a lifetime?

Answer 21

Tan is increased production of melanosomes and only affects the epidermis.
Tattoo pigment penetrates the dermis

Question 22

What is the difference between thin and thick skin?

Answer 22

Thick skin is hairless and found on palms and soles

Thin skin is hairy and is where skin care products normally applied

Question 23

What are the 4 types of activity in skin pharmacology?

Answer 23

antioxidants
anti-inflammatory
enzyme modulation
immune enhancement

Question 24

What are the 3 skin active targets for skin physiology

Answer 24

Processing of xenobiotics
immunological responses
UV radiation responses

Question 25

What are the 3 routes of skin penetration

Answer 25

direct transdermal (up to 99.9%)
transfollicular (0.1 - > 50%)
via eccrine gland

Question 26

What is the stratum corneum brick and mortar model

Answer 26

stacked coreneocytes with lipidic pathways

Question 27

What happens as cells move up the epidermis?

Answer 27

• cells proliferate and differentiate (mitotic division and cells flatten toward surface)
• dead, keratinized cells end up at surface - “keratinized stratified squamous”

Question 28

What are 7 skin penetration issues?

Answer 28

• Active ingredients must pass through stratum corneum
• Solubility parameter of SC ~ 8.
• Penetration depends on polarity of active and charge
• Penetration depends on hydration of SC for more hydrophilic materials
• Penetration depends on actives (m.w.

Question 29

What are the 6 skin care bases?

Answer 29

Emulsions (liquid/liquid dispersion)
Gels (polymer/thickener dispersion)
Solutions (water, alcohol, oil, silicone)
Suspensions (solid particle in liquid)
Sticks/solids
Powders

Question 30

What are the skin care OTC categories?

Answer 30

Sunscreen
Anti-acne
Skin Protectants
Skin Bleaching
External Analgesics
Dandruff/Seborrhea/Psoriasis
Anti-perspirants
Hair-growth

Question 31

define emulsion

Answer 31

A system of two (or more) immiscible materials (usually liquids) in which one material (the dispersed/internal phase) is suspended/dispersed throughout the other material (the continuous/external phase) in separate droplets

Question 32

define oil in water emulsion (O/W)

Answer 32

the dispersed phase of the emulsion is oil

Question 33

define water in oil emulsion (W/O)

Answer 33

the dispersed phase of the emulsion is water

Question 34

define emulsifier

Answer 34

A surface active agent (surfactant) which reduces the interfacial tension between the dispersed (internal) phase and the continuous (external) phase

Question 35

define emulsion interface

Answer 35

boundary between 2 phases

Question 36

What does INCI stand for

Answer 36

International Nomenclature Cosmetic Ingredient