Integumentary Test

parts of the skin

skin, hair, nails, associated structures (glands, vessels, nerves)

protection, communication, temperature regulation, vitamin D, excretion, immunity

functions of the skin

organs

skin is one of the largest _______________ in the body

2

How many layers are in the skin?

epidermis, dermis

layers of the skin

membrane

due to being a double layer of cells and tissue it is also considered a ________________

hypodermis

underlying the dermis

hypodermis

consists of loose CT with collagen and elastic fibers

hypodermis

types of cells: fibroblasts, adipose cells, macrophages

hypodermis

also called the subcutaneous tissue or the superficial fascia

hypodermis

contains about half of the body's fat

energy source, insulation, padding

functions of the hypodermis

hypodermis

very vascular

dermis

cells aren't crowded

dermis

the inter cellular material contains a lot of collagen and elastic fibers

collagen

fiber in the dermis that forms a dense mat, giving it the consistency of a firm, wet sponge

elastic

fibers that provide elasticity

dermis

gives structural strength; CT with many fibers, fibroblasts, macrophages; some adipocytes and blood vessels

dermis

contains nerves, blood vessels, hair follicles, smooth muscles, glands, and lymphatic vessels

sensory functions

pain, itch, tickle, temperature, touch, pressure, two-point discrimination

2

How many layers does the dermis have?

reticular

4/5 of dermis; made up of dense irregular CT (prevents stretching and tearing)

reticular

(dermis) reticular and elastic fibers to allow the skin to stretch

reticular

(dermis) its protein fibers provide strength, extensibility and elasticity

reticular

(dermis) includes many accessory organs within or have them extending through

papillary

1/5 of dermis, superficial (outer)

papillary

(dermis) areolar with lots of elastic fibers

dermal papillae

finger-like projects that extend towards the epidermis and strengthens the connections between layers

papillary

(dermis) creates contours in the surface called friction ridges (fingerprints)

papillary

(dermis) contains touch receptors and free nerve endings sensing pain

Meissner's corpuscles

sensitive touch receptors in the dermis

Clevage (tension) lines

elastin and collagen fibers oriented in some directions more than in others (important in surgery)

parallel

if incision is made _________________ to lines, there is less gapping, faster healing and less scar tissue

dermal tears

skin is overstretched, striae (stretch marks) occur

epidermis

is in a continual state of regeneration (mitosis)

epidermis

cells form a waterproof, protective wrap over the body's surface

epidermis

avascular because it's nourished by diffusion from capillaries of the papillary layer of the dermis

basement membrane

separated from the dermis by the __________________________________

45

the epidermis renews itself every ____________ days

keratinocytes

(epidermis) most cells, produce keratin for strength and waterproofing

melanocytes

(epidermis) cnotribute to skin color; prevent DNA mutation from UV radiation

freckles, moles

accumulation of melanin forms ________________ and ________________.

Langerhan's Cells

(epidermis) part of the immune system

Merkel's Cells

(epidermis) detect light, touch, and superficial pressure

desquamate

cells of the deeper layers undergo mitosis; as they move toward the surface, older cells slough off

keratinization

as cells move outward through the layers, they fill with keratin, die, and serve as a layer that resists abrasion and forms permeability

corneum, lucidium, granulosum, spinosum, basale

List the 5 layers of the epidermis in order from surface to deep (neglect the word stratum).

stratum basale

deepest portion of the epidermis and single layer of columnar cells

stratum basale

high mitotic activity

stratum basale

cells become keratinized

stratum spinosum

multiple layers of cuboidal cells with limited cell division

stratum spinosum

desmosomes - molecular bridges that connect them to adjacent cells giving them a spiny appearance

stratum spinosum

contains Langerhans macrophages

stratum granulosum

also contains Langerhan's; 3-5 rows of partially flattened cells containing small protein granules - keratohyalin (helps with keratin)

stratum granulosum

in superficial layers nucleus and other organelles degenerate and cell dies

stratum lucidum

found only where "thick skin" is like the palms and soles

stratum lucidum

3-4 rows of flattened, dead cells that are mostly transparent (ghosts_ and completely keratinized; thin clear zone

stratum corneum

most superficial layer; 20-50 rows of flattened, dead cells that are continuously being sloughed off

stratum corneum

consists of cornified cells (dead cells containing an envelope filled with soft keratin)

stratum corneum

tough, waterproof protection from this epidermal layer

3-4 weeks

How long does it take for cells produced in the stratum basale to migrate to the surface and be sloughed off

impermeable

the keratin barrier is NOT ____________________-

softens

after soaking keratin in water for a long period of time, it ______________________, making it more permeable to water; water leaves cell and skin appears temporarily wrinkled

thick skin

what type of skin has all 5 epidermal layers

thick skin

this type of skin is found in areas subject to pressure or friction likes the palms, soles, and fingertips

thick skin

the papillae of the underlying dermis are in parallel rows that shape the overlying epidermis into fingerprints and footprints

thin skin

more flexible of the two skin types, covers the majority of the body (local response to friction and pressure)

callus

increase in number of layers in the stratum corneum; when this occurs over a bony prominence, a corn forms

skin color

What is determined from pigments, blood circulating through skin, and thickness of the stratum corneum?

melanin

provides for protection against UV light; colored brown to black, may be yellowish or reddish

melanocytes

a mature melanin-forming cell; processes extend between keratinocytes

albinism

a recessive genetic trait resulting in a deficiency or absence of pigment; production determined by genetics, hormones, and exposure to light

hemoglobin

red, oxygen carrying pigment in erythrocytes (RBCs)

carotene

yellow pigment; from vegetables; accumulates in stratum corneum, in adipose cells of dermis and hypodermis

blood

imparts a reddish hue and increases during blushing, anger, inflammation

cyanosis

blue color caused by a decrease in blood-oxygen content

decubitus ulcer

bedsores, blood flow is restricted where the body has constant pressure on bed; cells die

dermis

For tattoos to be permanent, what layer must the ink be injected into?

hair

What is found everywhere on the body except for palms, soles, distal segments of fingers, etc.?

shaft

portion of the hair that protrudes above the skins surface

root

portion of the hair located below the surface; lies within the follicle

medulla

central axis of the hair

cortex

forms bulk of hair, middle layer

cuticle

forms the hair's surface

hair follicle

dermal root sheath and epithelial root sheath make this up

dermal root sheath

part of dermis that surrounds the epithelial root sheath

epithelial root sheath

sheath with internal and external parts

internal

In/external portion of epithelial root sheath contains the stratum basale that may remain after injury and supply a source of new epidermis?

white bulb

when hairs are pulled out, the internal part comes out and is visible as a _______________________

hair bulb

contains internal matrix of the hair and the dermis projects into it

internal matrix

part of the hair bulb that is the source of hair growth

blood supply

dermis projects into the bulb and is the _____________________

hair growth

is influenced by nutrition, hormones, and blood flow

growth

hair stage where cells are added at the base and hair elongates (avg. rate is 0.3 mm/day)

rest

hair stage where the follicle shortens and holds hair in place, then the hair falls out of the follicle and new hair begins

permanent hair loss

pattern baldness is the most common cause for this

hair color

What is caused by varying amounts and types of melanin?

melanin

What pigment can be black, brown and red?

dark

What color(s) is hair that contains true melanin?

blonde, red

What color(s) is hair whose melanin contains iron and sulfur?