The Skin CMR

Question 1

skin weight

Answer 1

10 pounds

Question 1

skin average surface area

Answer 1

20 sq ft

Question 2

four categories of skin function

Answer 2

1. protection
2. sensation
3. temp regulation
4. metabolic function

Question 3

skin function: protection

Answer 3

barrier from pathogens, chemicals, physical insults, radiation, and elements. Almost entirely waterproof.

Question 4

skin function: sensation

Answer 4

collection of sensory data; general sensory afferent nerve endings in skin provide sensations you feel when you cut or pinch a finger, touch a hot surface, etc. nerve endings are sensitive to pain, pressure, and temp

Question 4

Skin function: temp regulation/water ret
to help warm you up . . .

Answer 4

blood vessels constrict, reducing blood flow to outer skin, retaining warmth.

Question 4

Skin function: temp regulation/water ret
to help cool you down . . .

Answer 4

1. blood vessels dilate in skin, increasing blood flow to skins surface, allowing heat to escape
2. sweat glands in the skin increase their secretions, providing cooling as sweat evaporates on the surface.

Question 4

regular body temp

Answer 4

98.6 F (37 C)

Question 5

skin function: metabolic

Answer 5

1. synethesis of dehydrocholesterol -UV-> previt D -> vit D
2. abosrption of medications

Question 6

deficiency in vit D causes

Answer 6

deformities of rickets, increased risk for osteoporosis

Question 7

3 distinct regions of the skin

Answer 7

epidermis, dermis, subcutis

Question 8

external, thinner region of the skin

Answer 8

epidermis

Question 8

inner, thicker region of the skin

Answer 8

dermis

Question 9

fat layer of the skin

Answer 9

subcutis

Question 10

beneath the subcutis is

Answer 10

adipose tissue that binds to muscle

Question 11

derm/o meaning, darmat/o. cutane/o

Answer 11

skin

Question 12

epidermis

Answer 12

thin, outer region of the skin made up of dense stratified squamous epithelial tissue. usually in 4 strata.

Question 13

4 strata of the epidermis

Answer 13

1. strata corneum
2. strata granulosum
3. stratum spinosum
4. stratum germinativum

Question 14

in psoriasis, which layer is thickened?

Answer 14

epidermis

Question 15

outermost layer of the epidermis, serves as an important mechanical barrier to the external environment. composed of dead flattened cells that have undergone keratinization, and contains keratin, which resists abrasion and forms thick protective layers on skin surfaces subject to friction.

Answer 15

stratum corneum

Question 16

waterproof protein found in the cytoplasm in stratum corneum

Answer 16

keratin

Question 17

calluses are thick areas of

Answer 17

keratinized cells

Question 18

horny layer of skin

Answer 18

stratum corneum

Question 19

deepest portion of the stratum corneum

Answer 19

stratum lucidum

Question 20

stratum lucidum

Answer 20

part of the stratum corneum, thin, translucent layer found in skin of soles, fingertips, and palms.

Question 21

second-most superficial layer of epidermis

Answer 21

stratum granulosum

Question 22

stratum granulosum

Answer 22

second-most superficial layer; composed of cells with large, visible granules in cytoplasm. these elongated, rectangular cells contain keratohyalin, which contributes to keratinizations

Question 23

stratum spinosum

Answer 23

third-most superficial layer; composed of 8-10 layers of polygonal cells attached to neighboring cells by intercellular bridges (spiny appearance). this is the midportion of the epidermis, cells closer to the surface of this layer become flattened

Question 24

third-most superficial layer of epidermis

Answer 24

stratum spinosum

Question 25

basal cell layer

Answer 25

stratum germinativum

Question 26

stratum germinativum

Answer 26

single layer of mitotically active columnar cells, which produce new cells at the same rate at which older keratinized cells are sloughed off, thus maintaining a balance. also contains melanocytes, responsible for melanin pigment

Question 27

how many days does it take to replace skin cells/

Answer 27

28

Question 28

melanin function

Answer 28

protects DNA, the dermis, and deeper tissues

Question 29

Skin type I color, photoreactive description

Answer 29

pale, always burns, never tans

Question 30

Skin type II color, photoreactive description

Answer 30

white, burns easily and tans minimally

Question 31

Skin type III color, photoreactive description

Answer 31

white (average), sometimes burns mildly, tans uniformly to light brown

Question 32

Skin type IV color, photoreactive description

Answer 32

beige/lightly tan; burns minimally, always tans well to moderately brown

Question 33

Skin type V color, photoreactive description

Answer 33

moderately brown/tan; rarely burns, tans easily to dark brown

Question 34

Skin type VI color, photoreactive description

Answer 34

dark brown/black; never burns, deeply pigmented

Question 35

dermis

Answer 35

thicker, underlying region of the skin. composed of fibrous, irregularly arranged connective tissue. in contrast to the epidermis, the dermis is rich in blood vessels and nerve endings, as well as skin appendages, hair follicles, eccrine sweat ducts, glands, and sebaceous oil glands

Question 36

2 layers of dermis

Answer 36

papillary (upper), reticular layer)

Question 37

papillary layer

Answer 37

upper dermis; consists of papillae arranged in ridges, fingerprints, footprints, etc

Question 38

reticular layer

Answer 38

lower dermis; tough, white collagenous fibers that provide durability. yellow elastin fibers provide tension and elasticity

Question 39

stretch marks from pregnancy/obesity are found in what layer

Answer 39

elastic fibers, reduced skin fat/collagen, esp in chronic UV exposure; changes in the reticular layer

Question 40

subcutaneous tissue

Answer 40

beneath the skin, loose connective tissue and adipose tissue that contains collagenous fibers that extend from the dermis into the subq tissue and over muscles or bone to firmly attach the 2 structures.

Question 41

the skin is considered an organ because it

Answer 41

consists of multiple structures working as a unit to perform critical/complex functions