Anatomy Ch. 4: Skin and Body Membranes

cover surfaces, line body cavities, form protective sheets around organs

cover surfaces, line body cavities, form protective sheets around organs

functions of body membranes

cutaneous, mucous, serous

list the epithelial membranes (3)

cutaneous membrane

epithelial membrane composed of epidermis and dermis; exposed to air and is dry

stratified squamos epithelium

tissue type of epidermis

dense irregular (fibrous) connective

tissue type of dermis

mucous membrane

epithelial membrane that lines all body cavities open to exterior (respiratory, digestive, urinary, reproductive); bathed in secretations or urine; absorption and secretion

epithelium / loose (areolar) connective tissue / lamina propria

mucous membrane is composed of ___ resting on a ___ membrane called a ____

stratified squamos epithelium (mouth, esophagus) or simple columnar (digestive)

tissue type of most mucosae

no

does the urinary tract secrete lubricating mucus?

serous membrane

epithelial membrane that lines open body cavities and compartments in ventral body cavity closed to exterior; occur in pairs (parietal and visceral)

layer of simple squamos resting on thin areolar connective

tissue type of serous membrane

parietal

serous layer that lines a specific portion of the wlal of the ventral body cavity

visceral

serous layer that covers the outside of the organ in that cavity

serous fluid

serous layers separated by ____ that allows the organs to slide easily across cavity walls and one another w/o friction or pain

peritoneum

serosa lining abdominal cavity and covering its organs

pleurae

serosa surrounding lungs

pericardia

serosa surrounding heart

synovial membrane

connective tissue membrane that lines fibrous capsules arround joints, provide a smooth surface, and secrete lubircating fluid, and line bursae and tendon sheaths

loose areolar connective (NO epithelial)

tissue type of synovial membrane

skin

another name for cutaneous membrane is?

maintains boudnaries by keeping water and others in and excess out; blocks bacteria; prevent heat loss

functions of skin

integumentary system

skin and its appendages (sweat and oil glands, hair, nails)

insulates and cushions deep organs; protection from mechanical damage (bumps and cuts), chemical damage (acids and bases), thermal damage (heat and cold), UV radiation (sun), and microbes; prevents water loss; regulate heat loss; excretion

functions of integumentary system

urea, salts, water / sweating / vitamin D, acid mantle (protect against bacterial invasion)

what does the skin excrete and when? What does the skin produce?

burn or friction causes separation of epidermis and dermis, and interstitial fluid accumulates in cavity

how do blisters form?

adipose

tissue type of hypodermis (subcutaneous)

no / skin / organs / nutrient storage / shock absorber / insulates / curves

Is the hypodermis part of the skin? It anchors the ____ to underlying ___ and provides a site for ____. It serves as a ____ and ____ the deeper tissues from extreme temp changes. Also results in women’s ____.

keratinocytes / desmosomes

most cells of the epidermis are this, which produce the fibrous protein that makes it a tough protective layer; they are connected by?

avascular

is the epidermis vascular or avascular?

stratum basale, spinosum, granulosum, lucidum, corneum

list the epidermis layers from deepest to most superficial

stratum basale

deepest epidermis layer connected to dermis along wavy border; contins most adequately noursihed cells; cells constantly dividing

stratum spinosum

epidermis layer in which cells contain thick bundles of intermediate filaments made of pre-keratin

sratum granulosum

epidermis layer in which cells are flattened, organelles are deteriorating, cytoplasm full of granules, and more keratinized

stratum lucidum

clear epidermis layer only present in areas where skin is hairless and thick (palms and soles)

accumulating keratin, water-repellent glycolipid secreted, distance from blood supply, inadequate nutrients and oxygen

reasons for epidermal cells dying in lucidum —>

stratum corneum

outermost epidermal layer 20-30 cell layers thick, accounting for ¾ of epidermis; shinglelike dead clels completely filled with keratin are cornified

abundance of tough keratin proteins

why is the stratum corneum a durable body coating

melanin / melanocytes / stratum basale

pigment that ranges in color from yellow to brown to black and produced by special spider-shaped cells called ____. found chiefly in ____.

freckles and moles

forms where melanin is concentrated in one spot

epidermal dendritic cells

important sentries that alert and activate immune system cells to a threat of bacteria or virus

merkel cells / merkel discs

found at epidermal-dermal junction and associated with sensory nerve endings and tough receptors called ____

leathery skin, depressed immune system, human herpesvirus 1 (cause cold sores), skin cancer

effects of excessive exposure to UV light

melanin

skin’s natural sunscreeen

dermis

your “hide”, strong, strethcy envelope that helps bind body together; composed of 2 major regions (papillary and reticular)

areolar connective tissue

tissue type of papillary dermis layer

dense irregular connective tissue

tissue type of reticular dermis layer

papillary layer / dermal papillae

superficial dermal region that is uneven and has peglike projections called ____ which indent epidermis

capillary loops / pain / touch

papillary layer may contain ____, which furnish nutrients to epidermis. others house ____ receptors (free nerve endings) and ____ receptors

papillary patterns

ridges of fingertips and gripping ability of fingers and feet caused by?

reticular layer

deepest skin layer containing blood vessels, sweat and oil gands, and deep pressure receptors called almellar corpuscles

cutaneous sensory receptors

tiny sensors located in skin that help with touch, pressure, temp, and pain receptors, prevent microbes from penetrating body

collagen

what type of fibers are responsible for toughness of dermis, attract water, and keep skin hydrated

elastic

what type of fibers give the skin elasticity and youth

number of collagen and elastic fibers decreases, and hypodermis (subcutaneous) layer loses fat leading to wrinklage

why does our skin age

vascular / homeostasis of body temp

is the dermis vascular or avascular and why is that important?

capillaries / swollen / red and warm / radiate from / bypasses / capillaries

When the body temp is high, ____ of the dermis become ____ with heated blood, and skin becomes ____ so that body heat can ____ skin surface. When temp low, blood _____ _____.

decubitus ulcers

occur in bedridden patients who are not turned regularly or who are dragged or pulled across the bed repeatedly

yellow, reddish brown, or black

color(s) of melanin in epidermis

sunlight exposure (leads to tan)

what stimulates melanocytes to produce more melanin pigment

melanosomes / keratinocytes / shields

as the melanocytes produce melanin, it accumulates in their cytoplasm in membrane-bound granules called ____. granules then move to ends of melanocyte spidery arms, where taken up by ____. Inside keratinocytes, melanin ____ DNA from UV damage

brown-toned / light

people who produce a lot of melanin have ____ skin and people with less have ___ skin

strtum corneum and subutaneous tissue

carotene is deposited in the

orange-yellow

what color is carotene pigment

dermal blood vessels

hemoglobin is found in

oxygen-rich hemoglobin in dermal blood supply flushes through transparent cell layers above

why does the skin of light people appear rosy

cyanosis

blood and skin appears blue whe hemoglobin poorly oxygenated (in light-skinned people); common during heart failure and breathing disorders

erythema

redness is also known as

reddened

fever, hypertension, inflammation, and allergy result in ____ skin

pallor/blanching

anemia, emotional stress, low blood pressure, and impaired blood flow result in ____ skin

jaundice (yellow cast)

an abnormal yellow skin tone signifying a liver disorder in which excess bile pigments accumulate in blood, ciculate thru body, and deposit in body tissues

bruise / vitamin C / hemophilia

black-and-blue mark where blood escaped from circulation and clotted in tissue spaces; tendency to do this may signify a ___ deficiency or ____

hematomas

clotted blood masses

skin apendages

include cutaneous glands, hair and hair follicles, and nails; physically located in dermis but produced by epidermal layer

cutaneous glands

exocrine glands that release secretions to skin surface via ducts; formed by stratum basale and pushed into deeper skin; 2 types (sebaceous and sweat)

sebaceous glands

oild glands found all over skin except palms and soles; ducts usually empty into hair follicle

sebum

product of sebaceous glands that is a mixture of oily substances and fragmented cells; lubricant to keep skin soft and moist and prevent hair brittling; kills bacteria

acne

sebaceous gland ducts blocked by sebum and infected

whitehead / blackhead

If sebum in ducts does not dry, ___ forms. If it oxidizes and dries, a ___ will form

seborrhea

“cradle cap”, overactivity of sebaceous glands

sweat / eccrine / apocrine

sudiferous glands, also known as ___, have 2 types: ___ and ___

eccrine glands

sweat gland that is more numberous and found all over; secretes sweat (water plus some slats, vitamin C, and traces of wastes and lactic acid)

inhibits bacterial growth

Why is it important that sweat is acidic? How does sweat reach the skin surface

eccrine glands

glands important in body’s heat regulation; supplies with nerve endings

appocrine glands

glands largely confined to axillary (armpit) and genitals; larger and ducts empty into hair follicles; secretions contain fatty acids and protectins; milky or yellowish color

bacteria uses proteins and fats as nuctrient sources

when does sweat stink?

palms, soles, nipples, lips

where is hair not found on body

T

T or F: Humans are born with as many hair follicles as they will ever have

guarding head against bumps, shielding eyes, keeping stuff out of resipratory tract

functions of hair

root

part of hair enclosed in hair follicle

shaft

part of hair projecting from surface of scalp or skin

matrix

hair forms by division of well-nourished stratum basale epithelial cells in ___

medulla

each hair made up of a central core called ___, consisting of large cells and air spaces

cortex

bukly layer composed of several layers of flattned cells surrounding medulla

cuticle

encloses cortex; formed by single layer of cells overlapping; most keratinized region

abrasion causes cuticle to wear at shaft tip and inner hair regions frizz out

how do split ends form

eyebrows / head / smooth / wavy / flatt / curly

hair is short and stiff in ____, long and flexible on ___. When hair shaft is oval, hair is ___ and ____. When shalft is ____, the hair is ___

hair follices

compound structures; inner epithelial root sheath composed of epihtlial and forms hair

fibrous sheath

outer dermal connective tissue that supplies blood vessels to epidermal protion and reinforces it

hair papilla / hair bulb

____ provides blood supply to the matrix in ___

arrector pili

small bands of smooth muscle cells that connect each side of follicle to dermal tissue…goose bumps