Flawless skin is everyone's dream. To achieve that we need to have basic understanding of the skin structure and our own skin type, then choose the right skin care product, and continuous using it for a period of time. Having the right attitude in taking care of our skin is very important. Here we have the basic understanding of the skin structure, to briefly explain what is function of our skin.

1. INTRODUCTIONTO SKIN
Part 1- Epidermis

2. SKIN ANATOMY
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3. EPIDERMIS
Stratum Corneum
Stratum Granulosum
Stratum Spinosum
Stratum Basale
Stratum Lucidum
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4. THE RELATION BETWEENTHESE 5 LAYERS
Stratum CorneumStratum GranulosumStratum SpinosumStratum Basale
Stage 1
Stage 2
Stage 3
Stage 4
1 2 3 4
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5. STRATUM BASALE
• Made up of keratinocyte stem cell.
• Undergoes mitosis division to
constantly renew epidermal cells.
• Half of the cells differentiate and
move to the next layer (stratum
spinosum) to begin the
maturation process- Keratinisation/
desquamation
• Other cell in stratum basale:
Melanocyte Keratinocyte

6. SKIN DESQUAMATION
• is a natural process where skin cells
are sloughed away and replaced.
• It takes approx. 28 days.
• The duration of keratinisation
process will vary with different
lifestyle, sun exposure, ageing and etc.
• Dead skin cells accumulation will
result in pigmentation, dull skin,
dehydration and etc. - Exfoliating can
help in normalise skin regeneration.

7. MELANOCYTE
• is a melanin producing cells.
• melanin is a pigment found in eyes,
skin, and hair.
• Function is to protect skin cells and
tissues from harmful UV radiation-
transform the UV energy to heat.
• Almost everyone has the same
amount of melanocyte,while the
size and amount of melanosomes
can be different.
• Most of the whitening products act
on the process of melanogenesis.
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8. STRATUM SPINOSUM
• Retaining moisture and protect
against foreign bodies and substances.
• Begin to synthesise keratin, which can
hold water and retain moisture.
• Langerhans cells to detect skin
penetration by foreign matter and
transport the invaders to the lymph
node.
• The malfunction/activation of
langerhans cells can lead to sensitive
skin.
Desmosomes

9. STRATUM GRANULOSUM
• Contain granules, which to bind keratin
filaments together.
• Lamellar bodies are formed in the
keratinocytes of stratum granulosum.
• When it matures to the stratum corneum,
enzyme degrade the outer layer of lamellar
bodies, releasing lipids such as ceramides,
essential fatty acids and cholesterol.
• The lipids fuse with stratum corneum to
form a continuous layer of lipids- called
lamellar lipid bilayer- which is lipid soluble.
• impermeable to water soluble substances.
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10. STRATUM CORNEUM
• Outermost layer of epidermis, consist of 15-20 layers dead cells.
• Corneocyte/Keratinocyte- protein complex that made of keratin.These keratin can hold large
amounts of water between fibre. Contain NMF.
• Natural moisturizing factor (NMF)- water soluble compound that absorb water from the
atmosphere to stay hydrate.Yet, they are easily leached from the cells with water contact.
• Intercellular lipid- consist of ceramide, free fatty acids and cholesterol. It can maintain the water
balance by trapping water molecule
• Corneodesmosome- Diversify desmosome that hold the corneocyte together
Brick and mortar structure

11. STRATUM CORNEUM
• Water content in stratum corneum should remain approx 15-20%.
• The main functions of stratum corneum are
• to provide hydration to skin and prevent loss of water through the water holding/
absorb properties and lipid bilayer.
• to protect skin against foreign bodies through the brick and mortar structure.
• The incomplete of stratum corneum can lead to several skin problems- such as dehyrated
skin, aging skin, sensitive skin, oily skin and etc.
Brick and mortar structure

12. SEBUM
• A combination of sebum that secrete by
the sebaceous gland and sweat.
• It’s slightly acidic (pH 4.5-6.5)
• Function:
• to inhibit the growth of bacteria due
to the acidic environment
• Prevent water loss from the epidermis
due to it’s waterproof nature
• Sebum is odorless, but it breakdown by
bacteria can product strong odor
• The incomplete of sebum can lead to
acne skin.Keratinocyte
Intercellular matrix
Sebum
Brick and mortar structure Image source: pinterest.com

13. CONTENT OF STRATUM CORNEUM
Sebum
Corneocyte/
Keratinocyte
Intercellular Matrix
41%Triglyceride
21% Wax esters
Amino acids
Lactic acid
Cholesterol
12% Squalane
Uric acid
80% Keratin protein
20% amino acids
Uric acid
NMF
Pyrrolidone Carboxylic Acid
55% Ceramides
Cholesterol
Free fatty acids
Keratinocyte
Intercellular matrix
Sebum
Brick and mortar structure

14. REVISION
Stratum basale
• Skin regeneration
• Secrete melanin
Stratum spinosum
• Provide nutrients
• Detect allegens
Stratum granulosum
• Provide structural protection
• to create skin barrier
Stratum corneum
• Provide hydration
• 1st layer to protect skin from
foreign bodies.
Stratum lucidum
• Reduces effect of friction
• Provides protection
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15. REFERENCE
• https://www.youtube.com/watch?v=OKosGSm7Ps4
• http://dermatology.about.com/
• http://www.taiwanlaser.com/
• http://www.wisegeek.com/
• https://www.wikipedia.org