Download Epithelial Coverings

In Vertebrae skin functions in protection
and temperature regulation
 In fish, reptiles, and a few mammals the
epithelium forms scales
 Several types of specialized glands
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› Mammary glands
› Sebaceous glands
› Sweat glands
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Skin produces many different structures
› Skin of birds produce or form feathers.
› Skin of mammals form hair, nails, or claws
Waterproof layer
 Deepest layer is the Stratum basale
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› Site for new skin cell production
› Some of these cells produce melanin
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Upper layer known as stratum corneum
› Cells in this layer are keratinized
› Keratin waterproofs skin and makes up hair
and nails

Contains blood vessels and other structures
› Collagen strengthens the skin yet allows flexibility
› Elastin gives skin its elasticity. Fibrous
scleroprotein found in elastic tissues such as walls
of arteries.
› The dermis contains
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Sensory receptors
Sweat glands
Oil glands
Hair follicles are embedded in it
Located at the base of the dermis
 This is a fatty layer important for insulation
(white fat).
 Infants, hibernating animals, and small
rodents that live in cold areas have
brown fat.
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› Brown fat produces heat
Athletes
foot
Impetigo
Psoriasis