A&P McGraw Hill Connect Ch.5: The Integumentary System

integumentary system

Consists of the skin, mucous membranes, hair, and nail

What are the 5 functions of the integumentary system?

1) protection

2) sensation

3) temp regulation

4) vitamin D production

5) excretion

what are the two major tissues of the skin?

epidermis and dermis

which layer is the superficial layer of the skin?

epirdermis

which layer is deep to the epidermis?

dermis

which layer is made of connective tissue?

dermis

which layer is made of stratified squamous epithelium?

epidermis

know the diagram of the skin

epidermis

demis

epidermis structure

Function: Protection, secretion, absorption

Structure: Simple Squamous Epithelial Tissue, Keratinocytes.

stratum corneum

Function: structural strength, prevents water loss

Structure: most superficial layer of epidermis, 25+ ;ayers of dead skin cells

stratum lucidum

Function: disperses keratohyalin aroudn keratin fibers

Structure: 3-5 layers dead skin cells, transparent, in thick skin

stratum granulosum

Structure: 2-5 layers flattened diamond cells

Function: produces keratohyalin granules, release lipids from cells

stratum spinosum

structure: 8-10 layers of many sided cells

fucntion: produces keratin fibers

stratum basale

structure: deepest stratum in epidermis, basement membrane, attatches epidermis to dermis

Dermis

deepest part of skin, composed of two layers, responsible for structural strength and flexibility

papillary layer

dermis layer responsible for fingerprints, made of loose connective tissue

reticular layer

Deeper layer of the dermis that supplies the skin with oxygen and nutrients, mat of collagen and elastic fibers

subcutaneous tissue

Not part of skin

Loose connective tissue that connects skin to underlying structures

what are the layers of the epidermis (Come, Lets Get Sun Burnt!)

stratum corneum

stratum luciduim

stratum granulosum

stratum spinosum

statum basale

melanocytes

produce the pigment melanin

keratinocytes

The most abundant epidermal cells, they function mainly to produce keratin.

langerhans cells

part of the immune system

merkel cells

touch receptors responsible for detecting light touch

keratinization

Process by which cells accumulate keratin

during keratinization, what happens to the cells?

they die, then accumulate as an outer layer of dead, hard cells, that makes a permeability barrier.

birthmarks

Congenital (present at birth) disorders of the dermal capillaries

ringworm

fungal infection that produces patchy scaling and inflammatory response in the skin

eczema

Inflammatory condition of the skin which may be acute or chronic, characterized by itching or burning, tiny papules and vesicles, oozing, crusting, and scaling

frostbite

damage to the skin and tissues caused by extreme cold

psoriasis

chronic skin condition producing red lesions covered with silvery scales

vitillo

development of patches of white skin where melanocytes are destroyed, by autoimmune response

alopecia areata

Autoimmune disorder that causes the affected hair follicles to be mistakenly attacked by a person's own immune system; usually begins with one or more small, round, smooth bald patches on the scalp.

skin cancer

a harmful, malignant growth on the skin

impetigo

small blister containing pus, easily rupture to form a thick, yellowish crust, usually affects kids

erysipelas

Swollen patches in the skin caused by the bacterium Streptococcus pyogenes

Decubitius Ulcers is a _________________

pressure ulcer (bedridden and wheelchair people)

acne

inflammatory disease of the skin involving the sebaceous glands and hair follicles

rubeola

Skin lesions; caused by a virus contracted through the respiratory tract; may develop into pneumonia or infect the brain, causing damage

rubella

skin lesions, usually mild viral disease contracted through the respiratory tract, very dangerous if contracted during pregnancy

shinges

painful skin lesions, caused by the chickenpox virus after childhood infection, can recur when the dormant virus is activated by trauma, stress, or another illness

chickenpox

skin lesions, usually mild viral disease contracted through the respiratory tract

cold sores

Skin lesions; caused by herpes simplex I virus; transmitted by oral or respiratory routes; lesions recur

genital herpes

Genital lesions; caused by herpes simplex II virus; transmitted by sexual contact

strata

regions of the epidermis

what are the layers of the epidermis? (deep to superficial)

stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, stratum corneum

the number of cell layers in each stratum and number of Strata in the skin depend on what?

the location in the body

layers of strata

stratum basale

stratum germinativum

what type of tissue is in the basement layer of the epidermis?

single layer of cuboidal or columnar cells

________ hold keratinocytes together

desmosomes

stratum spinosum

consists of 8-10 layers of many-sided cells

lamellar bodies

Lipid-filled, membrane-bound organelles

stratum granulosum

2-5 layers of flat, diamond-shaped cells

stratum lucidum

Clear, transparent layer of the epidermis under the stratum corneum

stratum corneum

the most superficial layer of the epidermis consisting of dead cells

cornfield cells

dead keratinocytes

Where is thick skin found?

found in areas subject to friction or pressure (palms and soles)

where is thin skin found?

everywhere except palms of hands and soles of feet

callus

an area where the stratum corner of the epidermis increases in thickness

corn

skin over bony prominences develop these

what three factors determine skin color?

pigment in the skin

blood circulating through the skin

thickness of stratum corneum

melanin

group of pigments responsible for skin, hair, and eye color

provides protection against UV light from the sun

melanocytes produce and package melanin into vesicles called _________.

melanosomes

racial variations in skin color are determined by what major factors?

- type of melanin produced

- amount of melanin produced

- size of melanosomes produced

- distribution of melanosomes

albinism

a recessive genetic trait that results from an inability to produce tyrosinase

erythema

condition of redness of the skin due to the increase in blood flow to the skin

carotene

yellow pigment

basal cell carcinoma

Most common and least severe type of skin cancer; often characterized by light or pearly nodules.

what are the three types of skin cancer?

basal cell carcinoma, squamous cell carcinoma, melanoma

basal cell carcinoma

squamous cell carcinoma

melanoma

squamous cell carcinoma

Type of skin cancer more serious than basal cell carcinoma; often characterized by scaly red papules or nodules.

melanoma

least common

black oink red purple

ABCDE rule of skin cancer

A- asymmetry; 2 sides of pigmented area do not match

B- border irregularity

C- color (pigmented area) is black, brown, too tan, sometimes red or blue

D- diameter is larger than 6 mm (size of pencil eraser)

E- elevation above skin surface

What does the dermis include?

free nerve endings for pain, itch, tickle, and temp

hair follicle receptors for light touch

pacinian corpuscles for deep pressure

messier corpuscles for light touch

ruffini end organs for sensing continuous touch or pressure

what two layers are in the dermis?

papillary and reticular

dermal papillae

projections of dermis that cause epidermal ridges

friction ridges

the markings on the fingertips that leave oily fingerprints on surfaces we touch

cleavage lines

directions in which the skin is most resistant to stretch aka cleavage lines

stretch marks

thickened tissue resulting from excessive stretching of skin due to:

Pregnancy

Weight gain

intradermal injection

injection placed just below the epidermis

intradermal injection

subcutaneous injection

made into the fatty layer just below the skin

subcutaneous injection

intramuscular injection

an injection into deep muscle tissue, usually of the buttock, thigh, or upper arm

intramuscular injection

terminal hairs

long, coarse, heavily pigmented hairs (scalp, eyebrows, and eyelashes)

vellum hairs

short, fine, pale hairs that develop on most of the body during childhood

which hair replaces the other in many body parts when puberty hits?

terminal overtakes vellus

lanugo

fine downy hair of newborn infant

hair shaft

hair bulb

medulla

cortex

cuticle

dermal root sheath

dense dermis surrounding the hair follicle

epithelial root sheath

Extension of the epidermis lying adjacent to hair root

Widens at deep end into bulge—source of stem cells for follicle growth