Skin, Hair and Nails

Skin 2 Layers of Skin Outer Epidermis Inner supportive Dermis 3 rd Layer of Subcutaneous Adipose

2 Layers of Skin

Outer Epidermis

Inner supportive Dermis

3 rd Layer of Subcutaneous Adipose

Epidermis Protective Stratified into several zones Basal cell layer = forms new skin cells Keratin = major ingrediant Melanin = # but amt of production varies Uniformly thin except on palms and soles Avascular

Protective

Stratified into several zones

Basal cell layer = forms new skin cells

Keratin = major ingrediant

Melanin = # but amt of production varies

Uniformly thin except on palms and soles

Avascular

Vesicle, Bulla

Skin Color Melanin Carotene pigment Vascular beds in the dermis Affected by skin thickness & edema

Melanin

Carotene pigment

Vascular beds in the dermis

Affected by skin thickness & edema

Dermis Supportive layer Collagen Elastic quality for stretching Nerves, sensory receptors, bld. vessels, lymphs Epidermis appendages = hair follicles, sebacceous glands, sweat glands embedded in the dermis

Supportive layer

Collagen

Elastic quality for stretching

Nerves, sensory receptors, bld. vessels, lymphs

Epidermis appendages = hair follicles, sebacceous glands, sweat glands embedded in the dermis

Hair Important because? Threads of keratin 2 types Vellus hair- over body Terminal hair

Important because?

Threads of keratin

2 types

Vellus hair- over body

Terminal hair

Glands Sebaceous Glands Sebum = protective lipid substance Lubricates hair& skin prevents water loss everywhere but palms & soles Sweat Glands Eccrine = skin surface- sweat Apocrine = thick, milky secretion – axilla, anogenital, nipples, navel.

Sebaceous Glands

Sebum = protective lipid substance

Lubricates hair& skin

prevents water loss

everywhere but palms & soles

Sweat Glands

Eccrine = skin surface- sweat

Apocrine = thick, milky secretion – axilla, anogenital, nipples, navel.

Nails Keratin Color Condition Shape, Profile sign

Keratin

Color

Condition

Shape, Profile sign

Function of Skin Protection Prevents penetration Perception Temperature regulation Identification Communication Wound repair

Protection

Prevents penetration

Perception

Temperature regulation

Identification

Communication

Wound repair

Function of Skin Absorption & excretion Vitamin D – ultraviolet light > cholesterol

Absorption & excretion

Vitamin D – ultraviolet light > cholesterol