Term
| What are the three major layers of the skin? |
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Definition
- Epidermis
- Dermis
- Hypodermis (superficial fascia) |
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Term
| What is the outermost protective shield of the body? |
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Definition
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Term
| What is the tough, leathery layer composed mostly of fibrous connective tissue? |
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Definition
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Term
| Only this layer is vascularized. |
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Definition
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Term
| How do nutrients reach the epidermis? |
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Definition
| By diffusing through the tissue fluid from blood vessels in the dermis. |
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Term
| The subcutaneous tissue just deep to the skin is known as the _____________. |
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Definition
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Term
True or False
The Hypodermis is not part of the skin. |
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Definition
| True- however it does share some of the sin's protective functions. |
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Term
| Why is the hypodermis also called the superficial fascia? |
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Definition
| Because it is superficial to the tough connective tissue wrapping of the skeletal muscles, consists mostly of adipose tissue. |
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Term
| Because of its fatty composition, this layer also acts as a shock absorber and an insulator that reduces heat loss from the body. |
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Definition
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Term
| This layer is a keratinized stratified squamous epithelium consisting of four distinct cell types and four or five distinct layers |
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Definition
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Term
| What is the chief role of keratinocytes in the epidermis layer? |
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Definition
| to produce keratin, the fibrous protein that helps give the epidermis its protective properties |
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Term
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Definition
| the fibrous protein that helps give the epidermis its protective properties. |
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Term
| Where do keratinocytes arise from in the epidermis layer? |
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Definition
| From a cell layer deep in the epidermis called the stratum basale. |
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Term
| Spider-shaped epithelial cells that synthesize the pigment melanin. |
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Definition
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Term
| Found in the deepest layer of the epidermis |
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Definition
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Term
| What happens when melanin granules accumulate of the superficial, or "sunny", side of the keratinocyte nucleus? |
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Definition
| They form a pigment shield that protects the nucleus from the damaging effects of ultraviolet radiation in sunlight. |
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Term
- star shaped
- arise from bone marrow and migrate to the epidermis |
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Definition
| Epidermal dendritic cells |
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Term
| These are also called Langerhans cells |
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Definition
| Epidermal dendritic cells |
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Term
| These cells ingest foreign substances and are key activators of our immune system. |
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Definition
| Langerhan Cells/ Epidermal dendritic cells |
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Term
| Functions as a sensory receptor for touch |
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Definition
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Term
| Covers the palms, fingertips, and soles of the feet. |
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Definition
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Term
| The five epidermis layers that cover thick skin. |
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Definition
1. Stratum Corneum
2. Stratum Granulosum
3. Stratum Spinosum
4. Stratum Basale
5. Stratum Lucidum |
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Term
| How many layers are in the think skin, and which layer is absent. |
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Definition
4 layers in the thin skin
Stratum Lucidum is absent |
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Term
| the deepest epidermal layer, is attached to the underlying dermis along a wavy borderline that reminds one of corrugated cardboard |
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Definition
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Term
Deepest epidermal layer firmly attached to the dermis
Single row of stem cells
Also called stratum germinativum: cells undergo rapid division
Journey from basal layer to surface |
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Definition
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Term
Cells contain a weblike system of intermediate prekeratin filaments attached to desmosomes
Abundant melanin granules and dendritic cells |
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Definition
| Stratum Spinosum (Prickly Layer) |
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Term
Thin; three to five cell layers in which the cells flatten
Keratohyaline and lamellated granules accumulate |
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Definition
| Stratum Granulosum (Granular Layer) |
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Term
In thick skin
Thin, transparent band superficial to the stratum granulosum
A few rows of flat, dead keratinocytes |
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Definition
| Stratum Lucidum (Clear Layer) |
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Term
20–30 rows of dead, flat, keratinized membranous sacs
Three-quarters of the epidermal thickness |
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Definition
| Stratum Corneum (Horny Layer) |
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Term
protect the skin against abrasion and penetration, and the glycolipid between its cells nearly waterproofs this layer.
They are familiar to everyone as the dandruff shed from the scalp and dander, the loose flakes that slough off dry skin.
The average person sheds 40lbs of this which account for the majority of our dust in our houses. |
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Definition
| Stratum Corneum (Horny Layer) |
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Term
| While walking barefoot in the barn, Jeremy stepped on a rusty nail that penetrated the depth of the epidermis on the sole of his foot, Name the layers the nail pierced from the superficial skin surface to the junction with the dermis. |
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Definition
| Since the sole of the foot has thick skin, the layers from the most superficial to deepest would be the Stratum Corneum, the Stratum Lucidum, Stratum Granulosum, Stratum Spinosum, and Stratum basale. |
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Term
| The stratum basale is also called the stratum germinativum, a name that refers to the major function of this cell layer. What is that function? |
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Definition
| The stratum basale undergoes almost continuous mitosis to replace cells lost by abrasion. |
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Term
| Why are the desmosomes connecting the keratinocytes so important? |
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Definition
| The skin is subjected to a lot of abrasion and physical trauma, The desmosomes, which are connecting junctions, help to hold the cells together during such stress. |
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Term
| Given that epithelia are avascular, what layer would be expected to have the best nourished cells? |
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Definition
| The stratum basale, which abuts the dermis where the blood supply is, has the best nourished cells. |
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Term
| The second major skin region, is strong, flexible connective tissue. Its cells are typical of those found in any connective tissue proper: fibroblasts, macrophages, and occasional mast cells and white blood cells. |
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Definition
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Term
| What are the two layers of the Dermis called? |
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Definition
| Papillary and Reticular Layer |
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Term
| Areolar connective tissue in which fine interlacing collagen and elastic fibers form a loosely woven mat that is heavily invested with small blood vessels. |
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Definition
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Term
| accounting for about 80% of the thickness of the dermis, is coarse, irregularly arranged, dense fibrous connective tissue. |
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Definition
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Term
| What layer of the dermis is responsible for producing fingerprint patterns? |
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Definition
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Term
| What cell component of the hypodermis makes it a good shock absorber? |
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Definition
| Fatty tissue in the hypodermis gives it insulating and shock-absorbing properties. |
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Term
| You have just gotten a paper cut. It is very painful, but it doesn't bleed. Has the cut penetrated into the dermis or just the epidermis. |
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Definition
| Because there is no bleeding, the cut has penetrated into the avascular epidermis only. |
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Term
| What three pigments contribute to skin color? |
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Definition
| Melanin, Carotene, and hemoglobin |
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Term
| Which pigment is made in the skin? |
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Definition
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Term
| a polymer made of tyrosine amino acids. Its two forms range in color from yellow to tan to reddish-brown to black. |
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Definition
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Term
| a yellow to organe pigment found in certain plant products such as carrots. It tends to accumulate in the stratum corneum and in fatty tissue of the hypodermis. Its color is most obvious on the palms and soles. |
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Definition
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Term
| the pinkish hue of fair skin reflects the crimson color of this oxygenated pigment. |
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Definition
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Term
| Melanin and carotene are two pigments that contribute to skin color. What is the third and where is it found? |
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Definition
| Hemoglobin, the pigment found in red blood cells found in blood vessles of the dermis. |
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Term
| What is cyanosis and what does it indicate? |
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Definition
| it is a bluish cast of the skin that indicates that hemoglobin in the red blood cells in the dermal capillaries is poorly oxygenated. |
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Term
| What alteration in skin color may indicate a liver disorder? |
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Definition
| Jaundice or a yellow cast to the skin due to the deposit of yellow bile pigments in body tissues may indicate a liver disorder. |
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Term
| Another name for sweat glands |
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Definition
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Term
| distributed over the entire skin surface except the nipples and parts of the external genitalia. |
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Definition
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Term
| Two Types of sweat glands |
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Definition
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Term
| Another name for Eccrine glands |
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Definition
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Term
| far more numerous and are particularly abundant on the palms, soles of the feet, and forehead. |
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Definition
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Term
| a hypotonic filtrate of the blood that passes through the secretory cells of the sweat glands and is released by exocytosis. |
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Definition
| Eccrine gland secretion (sweat) |
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Term
| Is sweat an acid or base? |
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Definition
| Acidic with a pH between 4-6. |
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Term
| Through which system is sweating regulated by? |
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Definition
| the autonomic nervous system |
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Term
| Where are the apocrine sweat glands found? |
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Definition
| in the axillary and anogenital areas |
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Term
| Sometimes these glands produce a yellow or milky color. |
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Definition
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Term
| Another name for sebaceous glands |
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Definition
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Term
| Simple branched alveolar glands that are found all over the body except in the thick skin of the palms and soles. |
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Definition
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Term
| softens and lubricates the hair and skin, prevents hair from becoming brittle, and slows water loss from the skin when the external humidity is low. |
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Definition
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Term
| What specific hormone secretes sebum? |
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Definition
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Term
| Which cutaneous glands are associated with hair follicle? |
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Definition
| Sebaceous (oil) glands and apocrine glands are associated with the hair follicles. |
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Term
| When Anthony returned home from a run in 85 degree weather, his face was dripping with sweat. Why? |
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Definition
| His sympathetic nervous system activated his eccrine sweat glands and caused heat-induced sweating in order to the cool the body. |
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Term
| What is the difference between heat-induced sweating and a "cold sweat," and which variety of sweat glands is involved? |
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Definition
| Heat-induced sweating occurs all over the body when we are overheated. A cold sweat is emotionally induced sweateing that begins on the palms, soles, and armpits and then sspread to other body area. Both types of sweating are produced by the eccrine sweat glands, but activity of apocrine sweat glands is also likely during a cold sweat. |
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Term
| Sebaceous glands are not found in thick skin. Why is their absence in those body regions desirable? |
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Definition
| The palms of the hands and soles of the feet are thick skin areas. It would be dangerous to have oily soles, and oily palms would decrease the ability of the hands to hang onto things. |
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Term
| Flexible strands produced by hair follicles and consist largely of dead, keratinized cell |
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Definition
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Term
| The region of hair where the portion in which keratinization is complete |
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Definition
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Term
| The region of hair where keratinization is still ongoing. |
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Definition
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Term
| Projects from the skin, extends about halfway down the portion of the hair embedded in the skin |
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Definition
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Term
| the remainder of the hair deep within the follicle |
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Definition
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Term
| Consists of large cells and air spaces. The only part of the hair that contains soft keratin. Is absent in fine hairs. |
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Definition
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Term
| A bulky layer surrounding the medulla, consists of several layers of flattened cells. |
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Definition
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Term
| Formed from a single layer of cells that overlap one another from below like shingles ona roof. This arrangement helps to keep neighboring hairs apart so that the hair does not mat. Most heavily keratinized part of the hair, provides strength and helps keep the inner layers tightly compacted. Tends to wear away at the tip of the hair shaft, allowing keratin fibrils in the cortex and medulla to frizz out, creating "split ends". |
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Definition
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Term
| Hair pigment is made by __________ at the base of the hair follicle and transferred to the cortical cells. |
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Definition
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Term
| Red hair is colored by the iron-containing pigment called ______ |
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Definition
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Term
| Gray or white hair results from???? |
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Definition
| Decreased melanin production and from the replacement of melanin by air bubbles in the hair shaft. |
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Term
| fold down from the epidermal surface into the dermis. In the scalp, they may even extend into the hypodermis. |
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Definition
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Term
| The deep end of the follicle below the skin surface, is expanded, forming a _______. |
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Definition
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Term
| A knot of sensory nerve endings called a _____________ wraps around each hair bulb. |
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Definition
| Hair follicle receptor AKA Root hair plexus |
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Term
| a nipple-like bit of dermal tissue, protrudes into the hair bulb. this contains a knot of capillaries that supplies nutrients to the growing hair and signals it to grow. |
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Definition
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Term
| The wall of a hair follicle is composed of an outer _______ ________ _____ ____, derived from the dermis |
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Definition
| Connective tissue root sheath |
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Term
| The wall of a hair follicle is composed of a thickened basement membrane called the _____ _____. |
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Definition
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Term
| The wall of a hair follicle is composed of an inner ____ ___ ____ derived mainly from an invagination of the epidermis. |
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Definition
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Term
| thins as it approaches the hair bulb, so that only a single layer of epithelial cells covers the papilla. |
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Definition
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Term
| Actively dividing area of the hair bulb that produces the hair. |
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Definition
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Term
| The cells that compose the hair matrix originate in a region called the _____ |
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Definition
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Term
| Associated with each hair follicle is a bundle of smooth muscle cells called an ________ "raiser of hair" |
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Definition
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Term
| What are the concentric regions of a hair shaft, from the outside in? |
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Definition
| The regions of a hair from outside in are the cuticle, cortex, and medulla. |
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Term
| Why is having your hair cut painless? |
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Definition
| There are no nerves in the hair, so cutting hair is painless. |
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Term
| What is the role of an arrector pili muscle? |
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Definition
| The arrector pili muscles pull the hair to the upright position. |
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Term
| What is the function of the hair papilla? |
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Definition
| The hair papilla contains a knot of capillaries that supplies nutrients to cells of the hair bulb. |
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Term
| Why is the lunule of a nail white instead of pink like the rest of the nail? |
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Definition
| The lunule of the nail is white because the thick nail matrix that underlies it blocks the rosy color of the dermal blood supply from showing though. |
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Term
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Definition
| Nails are hard because the keratin they contain is the hard keratin variety. |
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Term
| the least malignant and most common skin cancer. Stratum basale cells proliferate, invading the dermis and hypodermis. The cancer lesions occur most often on sun-exposed areas of the face and appear as shiny, dome shaped nodules that later develop a central ulcer with a pearly, beaded edge. This is relatively slow growing, and metastasis seldom occurs before it is noticed. |
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Definition
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Term
| the second most common skin cancer, arises from the keratinocytes of the stratum spinosum. The lesion appears as a scaly reddened papule that arises most often on the head, and hands. It tends to grow rapidly and metastasize if not removed. If it is caught early and removed surgically or by radiation therapy, the chance of complete cure is good. |
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Definition
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Term
| the most dangerous skin cancer because it is highly metastatic and resistant to chemotherapy. It is the cancer of melanocytes. 1/3 develop from preexisting moles. |
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Definition
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Term
| a tissue damage infliceted by intesne heat, electricity, radiation, or certain chemicals, all of which denature cell proteins and cause cell death in the affected areas. |
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Definition
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Term
| Only the epidermis is damaged. Symptoms include localized redness, swelling, and pain. Tend to heal in two to three days without special attention. Usually a sunburn. |
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Definition
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Term
| Injure the epidermis and the upper region of the dermis. Symptoms mimic those of first-degree burns, but blisters also appear. |
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Definition
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Term
| Skin grafting is usually necessary. No feeling from the burn. |
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Definition
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Term
| Which type of skin cancer develops from the youngest epidermal cells? |
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Definition
| Basal cell carcinoma develops from the youngest epidermal cells. |
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Term
| What name is given to the rule for recognizing the signs of melanoma? |
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Definition
| The ABCD rule helps one to recognize sings of melanoma. |
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Term
| The healing of burns and epidermal regeneration is usually uneventful unless the burn is a third-degree burn. What accounts for this difference? |
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Definition
| First and Second Degree burns can heal uneventfully by regeneration of epidermal cells as long as infection does not occur. Third degree burns destroy the entire epidermis and regeneration is not possible. Infection and loss of body fluid and proteins are problematic. |
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Term
| Although the anterior head and face represents only a small percentage of the body surface, burns to this area are often much more serious than those to the body trunk. Why? |
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Definition
| Burns to the face are serious because damage to the lungs can occur in such burns. |
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Term
| What is the source of vernix caseosa that covers the skin of the newborn baby? |
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Definition
| Vernix caseosa is a product of the sebaceous oil glands. |
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Term
| What change in the skin leads to cold intolerance in the elderly? |
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Definition
| Loss of subcutaneous fat, common in the elderly, leads to cold intolerance seen in this group of people. |
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Term
| How does UV radiation contribute to wrinkling of the skin? |
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Definition
| UV radiation degrades collagen and leads to loss of skin elasticity and water-holding capacity. |
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