Epidermis consists of four cell types: keratinocytes, melanocytes, dendritic, and tactile epithelial. Also consist of of five skin layers: Stratum basal, spinous, granulosum, lucidum, and corneum.
Keratinocytes- produces keratin, which gives skin protective properties. Arise in stratum basale.
Melanocytes- Synthesizes melanin. Also found in basale.
Dendritic- Ingest foreign invaders and one of key activators of immune system. Come from bone marrow and migrate to dermis.
Tactile Epithelial- Acts as sensory receptor for touch
Stratum Basale- Deepest epidermal layer. Contains single layer of stem cells and attached to underlying dermis.
Stratum Spinosum- Several cells thick and spiky in appearance. Contain most dendritic cells.
Stratum Granulosum- Keratinization begins in this layer. This helps form keratin and prevent water loss.
Stratum Lucidum- Only found in thick skin. Only has a few rows of dead keratinocytes.
Stratum Corneum- Most superficial. Protects against abrasion and penetration.