Integumentary system

Question 1

Functions of the integumentary system

Answer 1

1. protection (mechanical barrier, from water loss, against uv light)
2. sensation (detect temp, touch, pain)
3. temp regulation (cutaneous blood vessels allow for vasodilation/constriction, sweat production)
4. synthesis of vitamin d (promotes uptake of ca and p, promotes release from bones, reduces loss in urine)

Question 2

skin layers from superficial to deep

Answer 2

epidermis, dermis, subcutaneous (not part of the skin)

Question 3

epidermis

Answer 3

the most superficial layer of skin, stratified squamous, cells in several layers called strata, avascular

Question 4

epidermal strata frim superficial to deep

Answer 4

1. corneum (20-30 layers)
2. lucidum (varies)
3. granulosum (2-5 layers)
4. spinosum (8-10 layers)
5. basale (single layer)

Question 5

stratum basale

Answer 5

single layer of cuboidal/columnar cells, contains keratinocytes, melanocytes, Merkel cells

Question 6

stratum spinosum

Answer 6

many sided cells attached to each other by desmosomes, contain matured keratinocytes, melanocytes, langerhans cells

Question 7

stratum granulosum

Answer 7

keratinization begins in this layer, cells become flattened and diamond shaped, cells are oriented parallel to the skin surface

Question 8

stratum lucidum

Answer 8

several thin, clear layers of dead cells, layer is only present in thick skin of palms and soles of feet

Question 9

stratum corneum

Answer 9

several layers of dead, overlapping keratinized cells

Question 10

thick skin (epidermis)

Answer 10

has all 5 epithelial strata, found in areas subject to pressure and friction like the palms of hand, fingertips, soles of feet

Question 11

thin skin (epidermis)

Answer 11

fewer layers of cells than thick skin, more flexible, contains hair

Question 12

dermis

Answer 12

double layered (papillary = superficial, reticular= deeper), dense irregular tissue, collagen fibers predominate

Question 13

dermis- papillary layer

Answer 13

superficial layer of the dermis, made of areolar ct with lots of elastic fibers, contains projections called dermal papillae which extend toward epidermis

Question 14

dermis-reticular layer

Answer 14

deep layer of dermis consisting of dense irregular tissue, primarily collagen fibers, but has elastic fibers as well.

Question 15

cleavage lines

Answer 15

found in skin due to orientation of collagen and elastic fibers, more oriented one direction than others

Question 16

striae

Answer 16

form due to the rupture of the dermis, leave lines visible through the epidermis

Question 17

sebaceous glands

Answer 17

produce sebum which empties onto hair follicles and prevents drying of skin and hair, secretion stimulated by sex hormones

Question 18

eccrine glands

Answer 18

most common type of sweat gland, simple coiled tubular, function is thermoregulatory, found in palms of hands, all over body

Question 19

apocrine glands

Answer 19

open in hair follicles, superficial to sebaceous, found in axilla, genitalia, do not control body temp, produce body odor

Question 20

ceruminous glands

Answer 20

secrete cerumen, or ear wax

Question 21

hair zones

Answer 21

shaft (above surface of skin)
root (below surface of skin)
bulb (base of root)

Question 22

arrector pili

Answer 22

smooth muscle cells associated with each hair follicle, respond to cold or fright and produce goosebumps

Question 23

nails

Answer 23

consist of nail body and root, stratum corneum with hard keratin