Like this study set? Create a free account to save it.

Sign up for an account

Already have a Quizlet account? .

Create an account


the largest system of the body

16 % of body weight

the integument is ____% of the body's weight

1.5 to 2 m^2 in area

the integument is: _____ to ______ m^2 in area

Cutaneous Membrane, Accessory Structures

The integument is made up of 2 parts:

Outer Epidermis

Superficial epithelium (epithelial tissues)
[one component of the cutaneous membrane]

Inner Dermis

Underlying area of connective tissues
[one component of the cutaneous membrane]

Accessory Structures

Hair, nails, & multicellular exocrine glands
-->located primarily in the DERMIS & protrude through the EPIDERMIS to the SKIN SURFACE


An exensive network of blood vessels branches ( and sensory receptors that monitor touch, pressure, temperature, and pain provide valuable informaion to the CNS) through the _________


-Deep to the Dermis
-Superficial fascia/SUBCUTANEOUS layer


Seperates the integument from the deep fascia around other organs, such as muscles and bones

Protection, Excretion, Maintenance, Production, Production, Synthesis of Vitamin D3, Storage, & Detection

General functions of the skin & hypodermis:


The Skin & Hypodermis provide ________ of underlying tissues & organs against impact, abrasion, fluid loss, & chemical attack.


The Skin & Hypodermis provide __________ of salts, water, & organic wastes by integumentary glands.


The Skin & Hypodermis provide ____________ of normal body temperature through either insulation of evaporative cooling, as needed.


The Skin & Hypodermis provide ____________ of melanin, which protects underlying tissue from ultraviolet radiation.


The Skin & Hypodermis provide ___________ of keratin, which protects against abrasion and serves as a water repellent.

Synthesis of Vitamin D3

The Skin & Hypodermis provide ____________ of ___________ ____, a steroid that is converted to calcitriol, a hormone important to normal calcium metabolism.


The Skin & Hypodermis provide _________ of lipids in adipose tissue in the subcutaneous layer.


The Skin & Hypodermis provide _________ of touch, pressure, pain, & temperature stimuli, & the relaying of that information to the nervous system.

Stratified Squamous Epithelium

The Epithelium consists of a: __________ __________ ___________


The epidermis is dominated by:


The body's most abundant epithelial cells:


Keratinocytes contain large amounts of:

Thin skin

Covers most of the body surface; four layers of keratinocytes; about as thick as the wall of a plastic sandwich bag (about 0.08 mm)

Thick skin

Occurs in the palms of the hands and soles of the feet; contains a 5th layer (STRATUM LUCIDUM); has a much thicker superficial layer (STRATUM CORNEUM); is about as thick as a standard paper towel (about 0.5 mm)


Stratum means:

Stratum Basale, Stratum Spinosum, Stratum Granulosum, Stratum Lucidum, Stratum Corneum

The strata, in order from the basement membrane toward the free surface:

Stratum Basale

Innermost epidermal layer:

Stratum Germinativum

Another name for the Stratum Basale:


These attach the cells of the Stratum Basale (Germinativum) to the basement membrane that seperates the epidermis from the areolar tissue of the adjacent dermis:

Epidermal ridges

The Stratum Basale forms _________ ________, which extend into the Dermis (on the tips of fingers).
*Significant because the strength of the attachment is proportional to the surface area of the basement membrane (The more deeper the folds, the larger the surface area becomes.)

Dermal Papillae

Dermal projections that project into the Epidermis:
*Significant because the strength of the attachment is proportional to the surface area of the basement membrane (The more deeper the folds, the larger the surface area becomes.)

Ridge shapes; epidermal ridges

__________ __________ are genetically determined; the pattern of your __________ _________ is unique & does not change curing your lifetime.

Basal cells (Germinative cells)

Cells that dominate the Stratum Basale:
(Germinative cells)

Basal cells

Stem cells whose divisions replace the more superficial kertinocytes that are lost of shed at the epithelial surface:

Merkel cells

(Tactile cells) scattered among the cells of the stratum basale:

Tactile cells

Sensitive to touch; when compressed, they release chemicals that stimulate sensory nerve endings:


The brown tones of the skin result from the synthetic activities of pigment cells called:
*Distributed throughout the stratum basale, with cells processes extending into more superficial layers

Stratum Spinosum

Each time a stem cells divides, one of the daughter cells is pushed superficial to the stratum basale into the ________ ________, which consists of 8 to 10 layers of keratinocytes bound together by DESMOSOMES
*Name means "spiny layer"

Dendritic (Langerhans) cells

The stratum spinosum also contains ____________ cells which participate in the immune response by stimulating a defense against (1) microorganisms that manage to penetrate the superficial layers of the epidermis and (2) superficial skin cancers.

Stratum granulosum

-region superficial to the stratum spinosum
-"grainy" layer
-consists of 3 to 5 layers of keratinocytes derived from the stratum spinosum


A tough, fibrous protein, that is the basic structural component of hair and nails in humans:
*Protects against abrasion, and serves well as a water repellent


Protects underlying tissue from ultraviolet radiation:

Vitamin D3

A steroid that is converted to calcitriol, a hormone important to normal calcium metabolism:


Forms dense cytoplasmic granules that promote dehydration of the cell as well as aggregation & cross-linking of the keratin fibers

Stratum Lucidum

In the thick skin of the palms and soles, a glassy __________ __________ ("clear layer") covers the stratum granulosum.
*The cells in this layer are flattened, densley packed, largely devoid of organelles, and filled with keratin.

Stratum Corneum

Layer usually at the exposed surface of thick and thin skin; Normally contains 15 to 30 layers of keratinized cells; cells in each layer are tightly interconnected by desmosomes:


(Cornification) The formation of protective, superficial layers of cells filled with keratin; process occurs on all exposed skin surfaces except the anterior surfaces of the eyes:

7 to 10

It takes ____ to ____ days for a cell to move from the stratum basale to the stratum corneum.

Interstitial fluids

Water from ________ ________ slowly penetrates to the surface , to be evaporated into the surrounding air. You lose about _____ mL (about 1 pint) of water in this way each day.

Insensible Perspiration

Process of water loss (perspiration) that we are unable to see or feel

Sensible Perspiration

Process of water loss (perspiration) produced by active sweat glands that we are usually very aware of


When fluid accummulates into pockets, this forms:


A serious consequence of severe burns (If damage to the stratum corneum reduces its effectiveness as a water barrier, the rate of insensible perspiration skyrockets, & a potentially dangerous fluid loss occurs), and a complication in the condition known as:
*Excessively dry skin

Osmotic forces

When the skin is immersed in water, ______ forces may move water into or out of the epithelium

Osmotic flow

Swimming in the ocean reverses the ________ flow; because the ocean is a hypertonic solution, water leaves the body, crossing the epidermis from the underlying tissues.--> Long, slow process of dehydration.

Fresh water

Swimming or sitting in a bath of _______ water, causes the skin in the stratum corneum to swell due to the fact that this type of water is a hypotonic solution.

Carotene & melanin

Two main pigments of the epidermis:


Orange-yellow pigment that normally accumulates in epidermal cells; most apparent in the cells of the stratum corneum of light-skinned individuals, but also accumulates in fatty tissues in the deep dermis and subcutaneous layer.


Found in a variety of orange vegetables, such as carrots and squashes, and thus the skin of individuals who eat lots of carrots can actually turn orange from an overabundance of carotene.

Vitamin A

Carotene can be converted to Vitamin ____, which is required for both the normal maintenance of epithelia & the synthesis for photoreceptor pigments in the eye.


A brown, yellow-brown, or black pigment produced by meloncytes (pigment cells):


Involved in melanin production; located in the stratum basale; squeezed between or deep to the epithelial cells


Melanocytes manufacture melanin from the amino acid ________


Melanocytes package melanin in intracellular vesicles called _____________


Small, pigmented areas on relatively pale skin; irregular borders; represent the areas serviced by melanocytes that are producing larger-than-average amounts of melanin; tend to be most abundant on surfaces such as the face (due to greater exposure to the sun)


Similar to freckles; regular borders; contain abnormal melanocytes

Senile Lentigos (Liver Spots)

Liver spots is most common name; variably pigmented areas that develop on sun-exposed skin; older individuals with pale skin

Ultraviolet (UV) Radiation

This can damage DNA, causing mutations and promoting the development of cancer; produce burns, etc.


Over time, cumulative damage to the integument by UV exposure can harm ___________, causing impaired maintenance of the dermis --> leads to premature wrinkling


Blood contains red blood cells filled with the PIGMENT ________, which binds and transports oxygen in the bloodstream.
When bound to oxygen, it is bright red, giving capillaries in the dermis a reddish tint that is most apparent in lightly pigmented individuals


When the skin takes on a BLUISH coloration; most apparent in the areas of very thin skin, such as the lips or beneath the nails; canoccur in response to extreme cold or as a result of cardiovascular or respiratory disorders, such as heart failure or asthma


The liver is unable to excrete bile, so a YELLOWISH pigment accumulates in body fluids; advanced stages the skin and whites of the eyes turn yellow

Melanocyte-stimulating hormone

Some tumors affecting the pituitary gland secret large quantities of this; Hormone causes a darkening of the skin, as if the individual has an extremely deep bronze tan


Individuals lose their melanocytes; condition develops in about 1% of the population, & its incidence increases among individuals w/ thyroid gland disorders; primary problem is cosmetic

Addison's disease

The pituitary gland secretes large amounts of adrenocorticotropic hormone (ACTH), which is structurally similar to MSH. The effect of ACTH on skin color is similar to that of MSH.


When exposed to ultraviolet radiation, epidermal cells in the strattum spinosum and stratum basale convert a cholesterol-related steroid into:

Vitamin D3

Cholecalciferol is also called:


The _________ coverts cholecalciferol into an intermediary product used by the kidneys to synthesize the hormone CALCITRIOL


______________ is essential for the normal absorption of calcium and phosphorus by the small intestine; an inadequate supply leads to impaired bone maintenance and growth.

Skin cancers

________ cancers are the more dangerous, most common form of cancer.

Acitinic Keratosis

A scaly area on sun-damaged skin; it is an indication that sun damage has occurred, but it is not a sign of skin cancer.

Basal Cell Carcinoma

A cancer that originates in the stratum basale; the MOST COMMON SKIN CANCER.

Squamous Cell Carcinoma

Less common skin cancer, but almost totally restricted to areas of sun-exposed skin.

Malignant Melanomas

Are extremely dangerous skin cancer; grow rapidly and metastasize through the lymphatic system.

Asymmetry, Border, Color, Diameter

ABCD mnemonic to remember cancer's key characteristics:


A is for _____________: Melanomas tend to be irregular in shape; they are raised; may also ooze or bleed


B is for ___________: Generally irregular, and in some cases notched


C is for ___________: Melanoma is generally mottled, with any combination of tan, brown, black, red, pink, white, and blue tones.


D is for __________: Any skin growth more than about mm (0.2 in.) in diameter, or approximately the area covered by the eraser on a pencil, is dangerous.


Term usually reserved for essential organic nutrients that must be obtained from the diet because the body either cannot make them or makes them in sufficient amounts:

Vitamin D3

Alternative name for cholecalciferol:
*If cannot be produced by the skin and is not included in the diet, bone development is abnormal and bone maintenance is inadequate.


__________ is a disease caused by Vitamin D3 deficiency, and results in the bending of abnormally weak and flexible bones under the weight of the body, plus other structural changes.

Epidermal Growth Factor

(EGF) One of the peptide growth factors; Stimulation of stem cell divisions and epithelial repairs; Targets the Epidermis; Sourced from the duodenal glands; Widespread effects on epithelia throughout the body

Salivary glands & glands of the duodenum

EGF (Epidermal Growth Factor) is produced by the ________ glands & glands of the __________ (part of the small intestine)

Roles of the EGF (Epidermal Growth Factor)

*Promote divisions of basal cells in the stratum basale and stratum spinosum
*Accelerate production of keratin in differentiating keratinocytes
*Stimulate eidermal development and epidermal repair after injury
*Stimulate synthetic activity and secretion by epithelial glands


The _______ lies between the epidermis and the hypodermis.

Papillary & Reticular

The dermis has two major components:
(1) a superficial __________ layer
(2) a deeper ___________ layer

Papillary layer

________ layer of dermis: consists of areolar tissue, contains the capillaries, lymphatics, and sensory neurons that supply the surface of the skin.
*Derives its name from the dermal papillae that project between the epidermal ridges.

Reticular layer

___________ layer: deep to the papillary layer, consists of an interwoven meshwork of DENSE IRREGULAR CONNECTIVE TISSUE containing both COLLAGEN & ELASTIC fibers


An inflammation of the skin that primarily involves the papillary layer; inflammation typically begins in a part of the skin exposed to infection or irritated by chemicals, radiation, or mechanical stimuli.
*May cause no discomfort, or it may produce an annoying itch, such as in poison ivy.
*Other forms of the condition can be quite painful, and the inflammation can spread rapidly across the entire integument.

Collagen fibers

Very strong and resist stretching, but are easily bent or twisted (fibers)

Elastic fibers

Permit stretching and then recoil to their original length (fibers)

Water content

The ______ content of skin also helps maintain its flexibiility and resilence, properties collectively known as SKIN INTIGOR.

Wrinkles and sagging skin

Aging, hormones, & the destructive effects of uultraviolet radiation result in: ________ and _______ skin

Stretch marks

The skin wrinkles and creases, resulting in _______ _______ over time.


(Retin-A) Derivative of vitamin A that can be applied to skin as a cream or gel; drug was originally developed to treat acne, but it also increases blood flow to the dermis and stimulates dermal repair.

Cleavage lines

(Tension lines) The resulting pattern of fiber bundles in the skin:

Cutaneous Plexus

Network of arteries supplying the skin in the hypodermis along its border with the reticular layer of the dermis

Papillary Plexus

Small arteries form another network called the ________ _______, of the papillary layer; provides arterial blood to capillary loops that follow the contours of the epidermis-dermis boundary; these empty into a network of small veins that form a venous plexus deep to the papillary plexus


Alernative name for a bruise


Localized shedding of an epithelium

Decubitis uclers

(Bed sores) Affect patients whose circulation is restricted, especially when a splint, cast, or lying in bed continuously compresses superficial blood vessels; such sores commonly affect the skin covering joints or bony prominences, where dermal blood vessels are pressed against deeper structures..Chronic lack of circulation kills epidermal cells, removing a barrier to bacterial infection; eventually, dermal tissues deteriorate as well.


Cell death and tissue destruction; can occur in any tissue deprived of adequate blood flow

Sensory receptors

The integument is filled with _______ _________


_________ fibers in the skin control blood flow, adjust gland secretion rates, & monitor sensory receptors in the dermisand the deeper layers of the epidermis.

Tactile corpuscles

Receptors sensitive to light touch (located in the dermal papillae)

Lamellated corpuscles

Receptors sensitive to deep pressure and vibration (located in the reticular layer)


The connective tissue fibers of the reticular layer are extensively interwoven with those of the ______________


Consists of areolar and adipose tissue; quite elastic; superficial region contains larger arteries and veins; venous circulation of region contains substantial amount of blood-much of volume will shift to general circulation if these veins constrict

Blood reservoir

The skin is often desribed as a _______ reservoir.


(Lipoplasty) Sucutaneous adipose tissue is removed through a tube inserted deep into the skin ; relatively common and increasing in popularity

Subcutaneous; Hypodermic

____________ injection into the hypodermis by means of a ______ needle, is a useful way of adminstering drugs.


project above the surface of the skin almost everywhere, except over the sides and soles of the feet, the palms of the hands, the sides of the fingers and toes, the lips, and portions of the external genetalia.

2.5 million

The human body has about _____ million hairs, and 75% of them are on the general body surface, not on the head.

Hair follicles

hairs are nonliving structures produced in organs called _____ _________

Dense connective tissue sheath

Deep to the epidermis, each follicle is wrapped in a ______ ___________ ______ _______

root hair plexus

a _____ _____ _______ of sensory nerves surrounds the base of each hair follicle; as a reslt, you can feel the movemet of the shaft of even a single hair

Hair root

The protion of hair that anchors the hair into the skin-begins a the base of the hair at the HAIR BULB, and extends distally to the point at which the internal organization of the hair is complete, about halfway to the skin surface.

Hair shaft

part of hair which we see on the surface of the skin, extends from this halfway point to the exposed tip of the hair

Hair bulb

(in hair) mass of epithelial cells that forms a cap, called the:

Hair papilla

hair bukb surrounds this; a peg of connective tissue containing capillaries and nerves

Hair matrix

superficial cells of the hair bulb are responsible for producing the hair; they form a layer called the:


Basal cells near the center of the hair matrix divide, producing daughter cells that are gradually pushed toward the surface; daughter cells closest to the center of the matric form the:




Intermediate layer where daughter cells farther from the center of the hair matrix form


edges of the hair matrix form the _______, which will be the surface of the hair

hair growth cycle

hairs grow and are shed according to a ______ ______ _______

Club hair

at the end of the hair growth cycle, when the hair follicle become inactive, it is termed a _____ hair; the follcile gets smaller, and over time the connections between the hair matrix and _____ hair root break down; when another cycle begins, the follicle produces a new hair and the old hair is pushed to the surface and shed


Healthy adults with a full head of hair typically lose about _____ head hairs each day.


extremely fine and unpigmented hairs on a fetus

Vellus hairs

the fine "peach fuzz" hairs located over much of the body surface

Terminal hairs

heavy, more deeply pigmented and sometimes curly hairs-hairs on your head/eyebrows/eyelashes


Hair color/pigment is determined by the production of:

Seaceous glands

(oil glands) Holocrine glands that discharge an oily lipid secretion into hair follicles; these glands that communicate with a single follicle share a duct and are called SIMPLE BRANCHED ALVEOLAR GLANDS


secreted lipid product that contains tryglycerides, cholesterol, proteins, and elecrolytes; inhibits the growth of bacteria, lubricates abd protects keratin of the hair shaft, and conditions the surrounding skin.


(core) of the hair contains a flexible SOFT KERATIN


of hair contains thick layers of HARD KERATIN, which give the hair its stiffness


of hair, although thin, is very tough, & it contains HARD KERATIN

See more

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

Voice Recording