Term
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Definition
| Skin and its accessory structures: hair and nails, along with various glands, muscles, and nerves. |
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Term
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Definition
| Thermoregulation, protection, cutaneous sensations, excretion and absorption, synthesis of vitamin D. |
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Term
| structure of the skin (2 parts) |
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Definition
| 1. Superficial (epidermis) and 2. Deep (dermis, subcutaneous) |
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Definition
| This is the superficial layer of the skin. It is stratified squamous epithelium. It contains keratinocytes, melanocytes, langerhans cells, and merkel cells in a series of many layers. |
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Definition
| Cells in the epidermis that protect and produce lamellar granules which release a waterproofing sealant. |
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Definition
| Cells in the epidermis that produce melanin that contributes to skin color. They absorb UV rays. |
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Definition
| Cells in the epidermis that participate in immune response protecting the skin from microbe invasion. They can easily be damaged by UV light. |
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Definition
| Cells that are located in the deepest layer of the epidermis. They are the least numerous and fuction in the sensation of touch. |
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Term
| layers of the epidermis from deepest to most superficial |
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Definition
| Stratum basale, stratum spinosum, stratum granulosum, (stratum lucidum), stratum corneum. |
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Term
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Definition
| The deepest layer of the epidermis. It s composed of a single row of cuboidal or columnal keratinocytes and stem cells. Unable to regernate new skin if germinal portion is destroyed. Sometimes called stratum germinativum to indicate its role in the formation of new cells. |
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Definition
| Located in the epidermis, it has 8-10 layers of flattened keratinocytes, contains langerhans cells and melanocytes, and provides strength and flexibility. |
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Term
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Definition
| Located in the epidermis, it has 3-5 layers of lattened keratinocytes that undergo apoptosis ("programmed death"). This is the transition between the deeper and more superficial strata. Contains lamellar granules that make a water-repellant seal. |
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Term
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Definition
| Located in the epidermis, it has 3-5 layers of clear, flat, dead keratinocytes. It is present only in the fingertips, palms, and soles of the feet (where there is no hair). |
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Term
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Definition
| The most superficial layer of the epidermis containing 25-30 layers of dead, flat keratinocytes that are continuously shed and replaced by cells from deeper strata. Constant exposure to friction will cause formation of a callus. |
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Term
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Definition
| The accumulation of more keratin. Occurs over 2-4 weeks. |
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Term
| epidermal growth factor (EGF) |
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Definition
| A hormonelike protein that plays a role in epidermal growth. |
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Definition
| Second part of the skin deeper than the epidermis. It has blood vessels, nerves, glands, and hair follicles. Divided into papllary and reticular regions. |
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Definition
| Superficial region of the dermis. Contains dermal papillae, corpuscles of touch, and free nerve endings for sensations. |
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Term
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Definition
| Deep portion of the dermis. Composed of dense irregular connective tissue with collagen and elastic fibers. Contains adipose cells, hair follicles, arrector pili muscle, sebaceous and sudoriferous glands, veins, arteris, nerve fibers, and sensors. |
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Term
| structural basis of skin color (4) |
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Definition
| 3 pigments in dermis (melanin, carotene, and hemoglobin), amount of pigment the melanocytes produce, freckles (patches of accumulated melanin), and exposure to UV light (increases the synthesis of melanin in the organelle melanosome) |
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Definition
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Term
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Definition
| The type of skin that lacks epidermal ridges. It is not found on palms, palmar surfaces of digits, and soles. |
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Term
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Definition
| The type of skin that covers palms, palmar surfaces of digits, and soles. It has no hair follicles, arrector pili muscles, or sebaceous glands. It has more sweat glands and sensory receptors and stratum lucidum. |
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Term
| accessory structures of the skin (3) |
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Definition
| These develop from the embryonic epidermis. Hair (on most skin surfaces except palms, soles, palmar and plantar surfaces of digits), glands, and nails. |
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Term
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Definition
| Columns of dead, keratinized cells bonded together by extracellular proteins. Consists of shaft, root, and hair follicle. Develops from a matrix in the bulb. Associated with sebaceous glands, arrector pili muscles, and root plexuses. |
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Term
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Definition
| 15% of the time the hair is resting. The other 85% of the time it grows. The cycle can be altered by many factors. |
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Term
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Definition
| This is due primarily to the amount and type of melanin in the hair. |
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Definition
| Protection, decrease heat loss, and sensing light touch. |
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Term
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Definition
| These are plates of tightly packed, hard, keratinized epidermal cells. Consist of a body, free edge, root, lunula, eponychium, hyponychium, and matrix. |
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Definition
| Used to grasp, manipulate, and protect distal end of digits. |
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Definition
| The portion of the nail that is visible. |
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Definition
| The portion of the nail that may extend past the distal end of the digit (the white part). |
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Term
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Definition
| The portion of the nail that is buried in a fold of skin. |
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Definition
| The whitish crescent-shaped area of the proximal end of the nail body. |
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Definition
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Term
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Definition
| The portion of the nail beneath the free edge; a thickened region of stratum corneum which secures the nail to the fingertip. |
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Term
| kinds of skin glands (exocrine) (3) |
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Definition
| 1. Sebaceous, 2. Ceruminous, 3. Sudoriferous (eccrine and apocrine) |
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Term
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Definition
| Exocrine skin glands that are connected to hair follicles and produce sebum. |
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Term
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Definition
| Exocrine skin glands that modify sudoriferous glands in the external auditory meatus (ear canal). They produce cerumen (earwax). |
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Term
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Definition
| Exocrine skin glands that produce sweat. Can be divided into eccrine and apocrine. |
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Term
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Definition
| More common sudoriferous glands that regulate body temperature. Use ducts that open to surface of epidermis. |
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Term
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Definition
| Sudoriferous glands with ducts that open into hair folicles. Found in axilla, groin, areolae. |
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Term
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Definition
| Healing consists of a central portion extending deep down to the dermis. Wound edges involve only superficial damage to cells. A hormone (EGF) stimulates basal cells to divide and replace the ones that hve moved into the wound. |
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Term
| deep wound healing (dermis and subcutaneous layers) |
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Definition
| Healing involves 4 phases (inflammatory, migratory, proliferative, and maturation). Fibrosis can occur. |
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Term
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Definition
| First phase of deep wound healing where a blood clot forms in the wound and loosely unites the wound edges. |
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Term
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Definition
| Second phase of deep wound healing where the clot becomes a scab and epithelial cells come together beneath the scab to bridge the wound. |
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Term
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Definition
| Third phase of deep wound healing where extensive grownth of epithelial cells beneath the scab and continual growth of blood vessels occurs. |
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Term
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Definition
| Fourth and final phase of deep wound healing where the scab sloughs off once the epidermas has been restored to normal thickness. |
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Term
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Definition
| The process of scar tissue formation. |
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Term
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Definition
| Three layers of tissue from which a developing embryo differentiates: ectoderm, mesoderm, and endoderm. |
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Term
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Definition
| The primary germ layer from which the epidermis (hair, nails, skin glands) is derived. |
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Term
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Definition
| The primary germ layer from which the dermis, connective tissues, and blood vessels associated with the glad develop. |
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