INTEGUMENTARY SYSTEM Flashcards
What are the two layers of the skin?
epidermis and dermis
True or false: the dermis is 10-20 times thicker than the epidermis
True
___ provides protection, ___ provides structural strength
epidermis, dermis
The skin rests on the ___ tissue; a layer of connective tissue
subcutaneous
What type of tissue is the epidermis made of?
Stratified squamous epithelium
the cells change shape and chemical composition; it becomes filled with the protein keratin which makes them more rigid and durable
Keratinization
Enumerate the strata of the epidermis from most superficial to deep
stratum corneum
stratum lucidum
stratum granulosum
stratum spinosum
stratum basale
Consists of cuboidal or columnar cells; Undergoes mitotic division every 19 days
Stratum Basale
Has a flattened appearance; Accumulates lipid filled vesicles called lamellar bodies
Stratum Spinosum
Flat and diamond shaped; The cells accumulate more keratin and release the content of the lamellar bodies to the extracellular space
Stratum Granulosum
Thin, clear zone; The cells of this layer no longer have nuclei or organelles making cells stain more lightly
Stratum Lucidum
Skin that has all five layers of the epidermis
Thick skin
Skin that lacks the stratum lucidum
Thin skin
Most superficial layer; Consists of 25 or more layers of dead squamous cells filled with keratin joined by desmosomes
Stratum Corneum
sloughed cells from the surface of the scalp
Dandruff
formed when the layers of stratum corneum increases when subjected to friction
Callus
a cone-shaped structure that can form in body areas due to layering
Corn
What type of tissue is the dermis made of?
Dense collagenous connective tissue
___ and ___ are responsible for the strength of the dermis
Collagen and elastic fibers
orientation of collagen fibers in different directions; the skin is most resistant to stretch along these lines
Cleavage lines
damage in the dermis caused by overstretching
Stretch marks
projections on the upper part of the dermis; supplies nutrients to the dermis
Dermal papillae
patterns that shape the overlying epidermis
Friction ridges
delivers material to the blood slowly; administered by inserting a small needle at a shallow angle into the dermis
Intradermal injection
pinching the skin to form a tent and inserting a short needle into the adipose tissue
Subcutaneous injection
delivers material to the blood faster the intradermal or subcutaneous; inserting a long needle at a 90 degree angle into a muscle deep to the subcutaneous tissue
Intramuscular injection
True or false: the thickness of the stratum corneum is one of the factors that determine skin color
True
group of pigments responsible for skin, hair, and eye color; also provides protection against UV light from the sun
Melanin
produces melanin; Located between the stratum basale and stratum spinosum. Have long processes that extend between the epithelial cells deep into the epidermis
Melanocytes
vesicles where melanin is packaged
Melanosomes
recessive genetic trait that causes a deficiency or an absence of melanin resulting in fair skin, white hair, and unpigmented irises in the eyes
Albinism
a decrease of O2 in the blood producing a bluish color of the skin
Cyanosis
yellow pigment found in plants such as squash and carrots
Carotene
True or false: large consumption of carrotene rich food can turn the skin yellowish
True
Most common type of cancer
Skin cancer
Who are the people most likely to be affected by skin cancer?
Fair-skinned people and those older than 50
the most frequent type, with little chance that this type of cancer will spread or metastasize to other areas
Basal Cell Carcinoma
develops from cells immediately superficial to the stratum basale; results to nodular, keratinized tumor confined to the epidermis
Squamous Cell Carcinoma
rare form of skin cancer that arises from melanocytes, usually a in a preexisting mole; it is common and often fatal unless diagnosed and treated early in development
Malignant Melanoma
aka as the hypodermis
subcutaneous tissue
True or false: the subcutaneous tissue is part of the skin
False - it is not part of the skin but it attaches the skin to underlying bone and muscle
Acceptable percentage of body fat for females
21-30%
Acceptable percentage of body fat for males
13-25%
Attached or embedded into the skin
accessory skin structures
Found everywhere on the skin, except on the palms, soles, lips, nipples, parts of the genitalia, and the distal segments of the fingers and toes
hair
invagination of the epidermis that extends deep into the dermis
Hair Follicle
protrudes above the surface of the skin
Hair Shaft
part of the hair below the surface
Hair Root
expanded base of the root; where hair is produced
Hair Bulb
extension of the dermis that protrudes into the hair bulb; its blood vessels supply the hair bulb with nourishment to produce hair
Hair Papilla
surrounds the softer center
Cortex
soft center of the hair
Medulla
single layer or overlapping cells that holds the hair in the hair follicle
Cuticle
True or false: If the surface epidermis is damaged, the epithelial cells within the hair follicle can divide and serve as a source of new epithelial cells
True
smooth muscle cells; when it contracts it causes the hair to become more perpendicular to the skin’s surface and raises an area of the skin called a “goose bump”
Arrector Pili
True or false: hair is produced in cycles of growth and rest
True
stage where hair is formed by epithelial cells within the hair bulb; they divide and undergo keratinization
Growth stage
Stage wherein growth stops and the hair is held in the hair follicle
Resting stag
Eyelashes grow for about ___ days and rest for ___ days
30, 105
Scalp hairs grow for ___ years and rest for ___ years
3, 1-2
Major glands of the skin
Sebaceous and sweat glands
oily, white substance rich in lipids; lubricates the hair and the surface of the skin
Sebum
simple coiled tubular glands; Numerous in the palms and soles; Open onto the surface of the skin through sweat pores
Eccrine glands
True or false: Emotional sweating can occur in the palms, soles, armpits, and other places
True
simple, coiled tubular glands; Produce a thick secretion rich in organic substances; They open into hair follicles, but only in the armpits and genitalia
Apocrine Glands
When does the apocrine glands start to become active?
puberty
What causes body odor?
organic secretion of the apocrine glands being broken down by bacteria
A thin plate, consisting of layers of dead stratum corneum that contain a very hard type of keratin
Nail
visible part of the nail
Nail Body
part of the nail covered by skin
Nail Root
stratum corneum that extends onto the nail body
Cuticle
where the nail root extends distally
Nail Matrix
where the nail also attaches; epithelial tissue with a stratum basale that gives rise to the cells that form the nail
Nail Bed
whitish, crescent-shaped area at the base of the nail
Lunula
True or false: nails have a resting stage
False - unlike hair, nails doesn’t have a resting stage
The intact skin acts as a ___ to the diffusion of water from the deeper tissues to the epidermis.
barrier
___ acts as a heat insulator
hair
What stimulates the small intestine to absorb calcium and phosphate which are needed for normal bone growth and normal muscle function?
Vitamin D
True or false: Ammonia cannot be relased through sweat
False - along with urea and uric acid, ammonia can be excreted through our sweat but only in small amounts
a yellowish skin color resulting from liver damaged by a disease such as hepatitis
Jaundice
results when bacteria infecting the throat release a toxin into the blood that causes a reddish rash on the skin
Scarlet fever
the skin produces excess keratin and assumes a characteristic sandpaper texture
Vitamin A Deficiency
the nails lose their normal contour and become flat or concave
Iron-deficiency Anemia
high levels of lead in the hair can indicate what?
Lead poisoning
Injury to a tissue caused by heat, cold, friction, chemicals, electricity, or radiation
Burns
Part of the stratum basale remains viable, and regeneration of the epidermis occurs from within the burn area, as well as the edges of the burn
Partial-Thickness Burns
The epidermis and the dermis are completely destroyed, and recovery occurs from the edge of the burn wound.
Full-Thickness Burns
involve only the epidermis and are red and painful. Slight edema, or swelling, may be present
First-degree burns
First-degree burns heal in about how many days?
7 days (1 week)
damage both the epidermis and the dermis
Second-degree burns
Minimal second degree burns take about ___ weeks to heal, while burns deep into the dermis take ___ to heal.
2 weeks, several months
True or false: In all second-degree burns, the epidermis is damaged
True
the epidermis and dermis are completely destroyed.
Third-degree burns
True or false: you can still feel the pain of the burn in third-degree burns
False - sensory receptors would’ve already been destroyed
extremely severe burns that affect tissues deeper than the subcutaneous tissue
Fourth-degree burns
___ or complete removal of the damaged tissue is required with fourth-degree burns
Amputation
the epidermis and part of the dermis are removed from another part of the body and placed over the burn
Split skin graft
Why are skin grafts made artificially or from cadavers often unsuccessful?
Because the immune system detects them as foreign substances and rejects it