layers of the epidermis and dermis - integumentary system

stratum basale

• deepest layer of the epidermis 

• lies next to the epidermis 

• wavy borderline with the dermis anchors the two together 

• cells undergoing mitosis (cell division)

• daughter cells are pushed upward to become the more superficial layers 

stratum spinosum

second deepest layer of epidermis

stratum granulosum

third deepest layer of epidermis

stratum lucidum

• translucent cells containing keratin

• formed from dead cells of the deeper strata

• occurs only in thick, hairless skin of the palms of hands and soles of feet

• located right under the most superficial layer of epidermis 

stratum corneum

• outermost layer of the epidermis

• shingle-like dead cells are filled with keratin

what are the two layers of the dermis

papillary layer and reticular layer

papillary layer

• upper dermal region

• projections called dermal papillae

• some contain capillary loops

• others house pain and touch receptors

reicular layer 

• blood vessels 

• sweat and oil glands 

• deep pressure receptors 

what do the dermal papillae make up?

fingerprints

what types of fibers are located throughout the dermis?

collagen and elastic

what do the collagen fibers provide the skin with?

toughness

what do the elastic fibers provide the skin with?

elasticity