a&p mod 5 - integumentary system

integumentary system

skin, hair, nails

epidermis

composed of 4-5 layers of cells, (keratinocytes)

stratum basale

basal layer of epidermis composed of basal cells and contains melanocytes

melanocytes

produce melanin

stratum spinosum

"spiny" layer of skin that produces keratin

stratum granulosum

"grainy" layer composed of 3-5 layers of last living layer keratinocytes

stratum lucidum

"clear layer" of flattened, densely packed dead cells filled with keratin found only in thick skin

stratum corneum

outermost, protective region with 15-30 layers of dead keratinized cells

thin skin

covers most of body surface with 4 strata

thick skin

found on palms of hands and soles of feet with 5 strata

melanin

produced by melanocytes in stratum basale and creates brown, yellow-brown- or black pigment.

melanin function

protects skin cell dna and increases production with UV exposure

cyanosis

bluish discoloration of the skin due to less blood flow

jaundice

yellowing of the eyes, skin and mucous membrane due to high level of bilirubin

bilirubin

what the liver converts hemoglobin to

bruising

discoloration of the skin due to broken blood vessel underneath the skin

red bruising

oxygen bound hemoglobin

blue bruising

hemoglobin without oxygen

purple bruising

mix of red and blue bruising

green, yellow, and brown bruising

hemoglobin break down and processing

carotene

yellow-orange pigment of skin due to overconsumption of vegetables

basal cell carcinoma

most common form of skin cancer and least harmful and originates in stratum basale due to mutations caused by overexposure to UV radiation

malignant melanoma

extremely dangerous cancer where melanocytes grow rapidly and metastasize through the lymphatic system

Squamous Cell Carcinoma

malignant tumor of the squamous epithelium commonly from UV exposure

dermis

between the epidermis and hypodermis

papillary layer

composed of areolar tissues deep to epidermal ridges and contains capillaries, lymphatic vessels and sensory neurons, forms dermal papillae

reticular layer

composed of dense irregular connective tissue and contains blood vessels, lymphatic vessels, nerve fibers and accessory organs (hair follicles, sweat glands, oil glands)

subcutaneous layer

separates skin from deeper structures and dominated by adipose tissues (important energy storage site) and includes adipose tissue

fingerprints

patterns of epidermal ridges on surface of fingertips

burns

result from exposure to heat, friction, radiation, electrical shock and can compromise many essential skin functions

first degree burn

extends into hypodermis, most sunburns

second degree burns

extends into papillary layer of dermis, pin prick is painful

third degree burn

extends into hypodermis, nerves are dead so pin prick is not painful

split thickness graft

transfer of epidermis and superficial portions of dermis

full thickness graft

transfer of epidermis and both layers of dermis

auto graft

patient's own skin

allograft

donor tissue from cadaver

xenograft

animal skin

rule of nines

method of estimating percentage of surface area affected by bones, modified for children (dif body proportions)

terminal hairs

large, coarse, darkly pigmented (scalp, armpit, pubic region, male facial hair)

vellus hairs

smaller, shorter, delicate (general body surface)

hair follicle

complex structure composed of epithelial and connective tissue that forms a single hair

hair shaft

region of the hair beneath the skin surface that is disconnected from follicle wall

hair root

region of hair attached to follicle wall and anchors the hair

root hair plexus

sensory nerves surrounding the base of the follicle

arrector pili

smooth muscle attached to hair follicle, contraction pulls hair erect and increases insulation layer restricting heat loss

sebaceous gland

produces oil secretions to coat hair and skin surface

hair bulb

expanded base of hair follicle where hair growth occurs

hair papilla

connective tissue filled with blood vessels and nerves surrounded by hair bulb

hair matrix

actively dividing basal cells in contact with hair papilla

exocrine glands of the skin

deposits a secretion on the external surface of the body

sebum

oil, lubricates skin and hair shaft, antimicrobial

acne

blocked oil gland in which p. acne bacteria are able to multiply

whitehead

blocked oil gland where oil is covered and has not been oxidized

blackhead

blocked oil gland where the exposed oil has been oxidized

papule

small red bump causes by inflammed hair follicle

pustule

classic pimple where immune system has been attacking bacteria and pus develops from dead white blood cells

sweat glands

secretes sweat and functions to wash epidermal surface

eccrine sweat glands

thermoregulation and excretion, found in palms and soles

apocrine sweat glands

secretes sweat and phermones (starting at puberty) into hair follicle and found in mammary glands, axillae, nipple and pubic regions

nails

thick sheets of dead keratinized epidermal cells, limits distortion of digits under physical stress, protects exposed dorsal surfaces of fingertips and toes

integument changes with age

fewer melanocytes, thinner and drier epidermis, diminished immune response, slower skin repair, reduced blood supply

growth hormones

stimulates fibroblasts activity and collagen synthesis for growth of body

sex hormones

stimulates epidermal cell divisions, increasing epidermal thickness and accelerating wound repair

rickets

vitamin d/sunlight deficiency in children leads to flexible/bowed bones

decreased bone density

common in elderly, partially from insufficient dietary intake and increases risk fractures

inflammation phase

initial injury causes bleeding and mast cell activation, mast cells stimulate inflammation, produces swelling, redness, heat and pain

migration phase

cells of stratum basale divide and migrate along wound edges, macrophages remove debris and pathogens, forms blood clots

scab

blood clot formed at surface of wound

granulation tissue

combination of fibroblasts, blood clot and capillary network

proliferation phase

scab undermined by migrating epidermal cells, phagocyte activity almost complete, blood blot disintegrating, fibroblasts have formed collagen fibers and ground substance

scarring phase

scab is shed, epidermis complete, shallow depression marks injury site, fibroblasts continue to create scar tissue

scar tissue

inflexible, fibrous, noncellular material

tissues from superficial to deep

keratinized stratified squamous epithelium, areolar, dense irregular, adipose

layers of epidermis from superficial to deep (thick skin)

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

which layers are dead?

corneum and lucidum

free edge

part of nail we cut

nail root

where nails grow from

Where are keratinocytes located in the integument?

all layers of epidermis

epidermis provides

abrasion resistance

Eponychium

epithelial tissue that sticks out over the proximal portion of the nail and provides a smooth transition from integument to nail

Epidermal ridges are composed of what tissue?

Keratinized stratified squamous epithelial tissue

integument is made up of

Dermis, epidermis layers

Nail bed

epithelial tissue underneath a nail that provides color to the nail

Which of the following integumentary layers is superficial?

Papillary layer of the dermis

Which type of tissue is the papillary layer of the dermis made of?

Areolar

Which integument layer provides strength?

Reticular Layer of the Dermis

hypodermis

subcutaneous layer composed of adipose tissue and is an important energy site

basal cells

produce new epidermal cells

lunula

proximal, semi-circular, white portion of the nail

Lateral Fold / Groove

epithelial folds that cover the nail on either side

hyponychium

small skin attachment under the distal edge of the nail