Skin, Hair, and Nails
Anatomy and Physiology:
- The skin and accessory structures (i.e., hair, nails, sweat glands, and sebaceous glands)
form what is referred to as the integumentary system.
- The skin is an elastic, self-regenerating organ.
- Many functions including protection, retaining of body fluids and electrolytes, primary
contact for sensory input, regulation of temperatures, production of vitamin D, excretion
of sweat, urea, lactic acid; expression of emotion (blushing) and even repair of its own
surface wounds through the normal process of cell replacement.
Skin:
- Epidermis:
o Thin, Outermost layer
o Composed of stratified squamous epithelium.
o This layer is avascular meaning it has no direct blood supply
o The deepest layer of epidermis is the stratum germinativum – adjacent to the
dermis which provides a rich supply of blood
o Within this deepest layer of epidermis, active cell generation takes place
o Melanocytes – provides pigment for the skin and hair – acts as a shield against uv
radiation
- Dermis:
o Comprises of highly vascular connective tissue
o Blood vessels dilate and constrict in response to external heat and cold and
internal stimuli such as anxiety or hemorrhage, results in regulating body
temperature
o Contains sensory nerve fibers that react to touch, pain, and temperature
o Can range in thickness of 1 to 4mm in different parts of the body
- Subcutaneous (Hypodermis):
o Not actually skin tissue but a support structure – acting as an anchor for the
upper layers
o Composed primarily of loose connective tissue interspersed with subcutaneous
fat
o These fatty cells help to retain heat, provide a protective cushion, and provide
calories
Appendages:
Hair:
- Epidermal cells in the dermis form hair
- Consists of root, shaft, and follicle
- Melanocytes within the hair shaft provide color
, Nails:
- Epidermal cells converted to hard plates of keratin
- Free edge, the nail plate, and the nail root (site of growth)
- Tissue under the nail plate is highly vascular, providing the clues to oxygenation status
and perfusion
Eccrine Sweat Glands:
- Regulate body temperature by water secretion through the surface of the skin
- Most numerous and widespread sweat glands in the body
- Found in the palms of hands, soles of feet, and the forehead
- Controlled primarily by the nervous system
Apocrine Sweat Glands:
- Much larger and deeper than eccrine glands
- Found only in the axillae, nipples, areolae, anogenital area, eyelids, and external ears
- Begin secretion at puberty and strongly influenced by hormones
- In response to emotional stimuli, the glands secrete an odorless fluid containing protein,
carbs, and other substances
- Decomposition of apocrine sweat produces what we associate with body odor
Sebaceous Glands:
- These glands secrete a lipid-rich substance called sebum, which keeps the skin and hair
lubricated.
- The greatest distribution is found on the face and scalp but can be found in all areas of
the body (except the palms and soles)
- Sebum secretion, stimulated by sex hormone activity, accelerates during puberty and
varies throughout the lifespan
Health History
Present Health Status: “Have you noticed in changes of skin, hair or nails look or feel?”
Past Health History
Family History
Personal and Psychosocial History
Problem Based History
- Skin: Pruritis (Itching), Rash, Pain, Lesion or Changes in Mole, Change in color, Skin
texture, wounds
- Hair
- Nails
Anatomy and Physiology:
- The skin and accessory structures (i.e., hair, nails, sweat glands, and sebaceous glands)
form what is referred to as the integumentary system.
- The skin is an elastic, self-regenerating organ.
- Many functions including protection, retaining of body fluids and electrolytes, primary
contact for sensory input, regulation of temperatures, production of vitamin D, excretion
of sweat, urea, lactic acid; expression of emotion (blushing) and even repair of its own
surface wounds through the normal process of cell replacement.
Skin:
- Epidermis:
o Thin, Outermost layer
o Composed of stratified squamous epithelium.
o This layer is avascular meaning it has no direct blood supply
o The deepest layer of epidermis is the stratum germinativum – adjacent to the
dermis which provides a rich supply of blood
o Within this deepest layer of epidermis, active cell generation takes place
o Melanocytes – provides pigment for the skin and hair – acts as a shield against uv
radiation
- Dermis:
o Comprises of highly vascular connective tissue
o Blood vessels dilate and constrict in response to external heat and cold and
internal stimuli such as anxiety or hemorrhage, results in regulating body
temperature
o Contains sensory nerve fibers that react to touch, pain, and temperature
o Can range in thickness of 1 to 4mm in different parts of the body
- Subcutaneous (Hypodermis):
o Not actually skin tissue but a support structure – acting as an anchor for the
upper layers
o Composed primarily of loose connective tissue interspersed with subcutaneous
fat
o These fatty cells help to retain heat, provide a protective cushion, and provide
calories
Appendages:
Hair:
- Epidermal cells in the dermis form hair
- Consists of root, shaft, and follicle
- Melanocytes within the hair shaft provide color
, Nails:
- Epidermal cells converted to hard plates of keratin
- Free edge, the nail plate, and the nail root (site of growth)
- Tissue under the nail plate is highly vascular, providing the clues to oxygenation status
and perfusion
Eccrine Sweat Glands:
- Regulate body temperature by water secretion through the surface of the skin
- Most numerous and widespread sweat glands in the body
- Found in the palms of hands, soles of feet, and the forehead
- Controlled primarily by the nervous system
Apocrine Sweat Glands:
- Much larger and deeper than eccrine glands
- Found only in the axillae, nipples, areolae, anogenital area, eyelids, and external ears
- Begin secretion at puberty and strongly influenced by hormones
- In response to emotional stimuli, the glands secrete an odorless fluid containing protein,
carbs, and other substances
- Decomposition of apocrine sweat produces what we associate with body odor
Sebaceous Glands:
- These glands secrete a lipid-rich substance called sebum, which keeps the skin and hair
lubricated.
- The greatest distribution is found on the face and scalp but can be found in all areas of
the body (except the palms and soles)
- Sebum secretion, stimulated by sex hormone activity, accelerates during puberty and
varies throughout the lifespan
Health History
Present Health Status: “Have you noticed in changes of skin, hair or nails look or feel?”
Past Health History
Family History
Personal and Psychosocial History
Problem Based History
- Skin: Pruritis (Itching), Rash, Pain, Lesion or Changes in Mole, Change in color, Skin
texture, wounds
- Hair
- Nails
