# 4.2: Skin Models

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Thin skin

Thick skin

Layers of the skin:

Epidermis

• Stratum corneum
• Stratum lucidum
• Stratum granulosum
• Stratum spinosum
• Stratum basale

Dermis

• Papillary layer
• Reticular layer
• Layers beneath the skin (subcutaneous)

Hypodermis

• Skin structures:

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Dermal papillae

Hair follicle

• Root
• Shaft
• Hair follicle
• Papilla
• Arrector pilli (or piloerector m.)
• Bulb

Blood vessels

Nerve endings:

• Lamellar corpuscle
• Tactile corpuscle

Glands:

• Eccrine (merocrine) sweat gland
• Pore
• Duct
• Apocrine sweat gland
• Sebaceous glands

Nail

• Eponychium
• Hyponychium
• Free edge
• Lateral nail fold
• Proximal nail fold
• Lunula
• Nail bed
• Nail plate (body)
• Nail matrix
• Skin cells:

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Keratinocytes

Melanocytes

Fibroblasts

•  Tissues types:

Stratified squamous epithelium

Areolar CT

Dense irregular CT