Integument Layers and Subcutaneous Layer
Stratum lucidum
2-3 layers of anucleate, dead keratinocytes; seen only in thick skin (i.e., palms of hands, soles of feet)
Stratum granulosum
3-5 layers of keratinocytes with distinct granules in cytoplasm: keratinization begins in this layer
Reticular layer
Deeper layer of dermis; composed of dense irregular connective tissue; surrounds and supports hair follicles, sebaceous glands and sweat glands, nerves, and blood vessels
Stratum corneum
Most superficial layer of epidermis: 20-30 layers of dead, flattened, anucleate, keratin-filled keratinocytes
Subcutaneous layer
Not considered part of the integument; deep to dermis; composed of areolar and adipose connective tissue
Stratum spinosum
Several layers of keratinocytes attached to neighbors by desmosomes; epidermal dendritic cells present
Stratum basale
Single layer of cuboidal to low columnar keratinocytes in contact with basement membrane, cell division occurs here; also contains melanocytes and tactile cells
Papillary layer
Superficial layer of dermis; composed of areolar connective tissue; forms dermal papillae: houses capillaries and tactile receptors