Term
| Functions of the Integumentary System |
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Definition
PROTECTION
Body temperature regulation
Cutaneous sensations
Metabolic functions
Blood reservoir
Excretion |
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Term
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Definition
| Low pH secretions retard bacterial activity |
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Term
| Protection/Physical/mechanical barriers: |
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Definition
Keratin and glycolipids block most water and water- soluble substances
Limited penetration of skin by lipid-soluble substances, plant oleoresins (e.g., poison ivy), organic solvents, salts of heavy metals, some drugs |
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Term
| Protection/Biological barriers |
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Definition
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Term
| Function/Body temperature regulation |
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Definition
~500 ml/day of routine perspiration (at normal body temperature)
At elevated temperature, dilation of dermal vessels and increased sweat gland activity cool the body |
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Term
| Function/Cutaneous sensations |
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Definition
| Temperature, touch, and pain |
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Term
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Definition
| Synthesis of vitamin D precursor and collagenase |
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Term
| Function/Blood reservoir— |
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Definition
| up to 5% of body’s blood volume |
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Term
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Definition
| nitrogenous wastes and salt in sweat |
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Term
| Integument Consists of three major regions: |
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Definition
Epidermis—superficial region
Dermis—middle region
Hypodermis (superficial fascia)—deepest region
Subcutaneous layer deep to skin (not technically part of skin)
Mostly adipose tissue |
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Term
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Definition
Keratinized stratified squamous epithelium
Cells of epidermis
Keratinocytes—produce fibrous protein keratin
Melanocytes
10–25% of cells in lower epidermis
Produce pigment melanin
Tactile (Merkel) cells—touch receptors |
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Term
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Definition
Most superficial layer s of dead
cells represented only by flat membranous
sacs filled with keratin
Protects from abrasion and penetration
Waterproofs
Barrier against biological, chemical, physical assaults |
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Term
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Definition
Three to five layers of flattened cells,
organelles deteriorating; cytoplasm full of
granules |
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Term
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Definition
Several layers of keratinocytes
Cells contain thick bundles of
intermediate filaments made of pre-keratin
prickly. |
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Term
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Definition
Deepest epidermal layer; one row of actively
mitotic stem cells; Active stem cells – 25-45
days to the skin surface |
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Term
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Definition
Strong, flexible connective tissue
2 layers: papillary, reticular |
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Term
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Definition
Areolar connective tissue with collagen and elastic fibers and blood vessels
Dermal papillae contain:
Capillary loops
Meissner’s corpuscles
Free nerve endings |
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Term
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Definition
~80% of the thickness of dermis
Collagen fibers provide strength and resiliency
Elastic fibers provide stretch-recoil properties |
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Term
| Three pigments contribute to skin color: |
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Definition
melanin
Carotene
Hemoglobin |
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Term
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Definition
Sweat glands
Oil glands
Hairs and hair follicles
Nails |
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Term
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Definition
Two main types of sweat (sudoriferous) glands
Eccrine
Apocrine
Eccrine sweat glands—abundant on palms, soles, and forehead
Sweat: 99% water, NaCl, vitamin C, antibodies, dermcidin, metabolic wastes |
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Term
| appendages/sweat glands types 2 |
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Definition
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Term
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Definition
Widely distributed
Most develop from hair follicles
Become active at puberty
Sebum
Oily secretion
Bactericidal
Softens hair and skin |
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Term
| appendages/hair/structure |
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Definition
Consists of dead keratinized cells
Contains hard keratin; more durable than soft keratin of skin
Hair pigments: melanins (yellow, rust brown, black)
Gray/white hair: decreased melanin production, increased air bubbles in shaft |
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Term
| appendages/NAILS/structure |
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Definition
| modification of the epidermis on the distal, dorsal surface of fingers and toes |
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Term
| Define the term histology. |
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Definition
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Term
| List and compare the four major tissue types. |
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Definition
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Term
| function and structure of different types of membranes |
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Definition
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Term
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Definition
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