Chapter 6

Question 1

integument

Answer 1

skin that covers the body; cutaneous membrane

Question 2

layers of integument (2)

Answer 2

epidermis and dermis

Question 3

five strata of epidermis

Answer 3

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

Question 4

layers of cells in each strata? (no specific number, just rough estimates)

Answer 4

basale - one
spinosum - more than one
granulosum - 3-5 layers
lucidum - 2-3 layers (few)
corneum - up to hundreds of layers

Question 5

“basement” layer, single layer of cuboidal cells

Answer 5

stratum basale

Question 6

what kind of cells are in the basal layer? (4)

Answer 6

keratinocytes, melanocytes, tactile/merkel cells, stem cells

Question 7

most abundant cell in epidermis

Answer 7

keratinocytes

Question 8

what do melanocytes do?

Answer 8

produce/store melanin

Question 9

“spiny” layer, several layers of keratinocytes, contains dendritic cells

Answer 9

spinosum

Question 10

function of dendritic cells?

Answer 10

immune functions

Question 11

“granular” layer, beginning of keratinization, 3-5 layers of keratinocytes

Answer 11

granulosum

Question 12

“clear” layer, 2-3 layers of flat keratinocytes, only found in thick skin

Answer 12

lucidum

Question 13

“hornlike” layer, most superficial layer of epidermis, 20-30 layers of keratinocytes

Answer 13

corneum

Question 14

how can you tell a cell is keratinized?

Answer 14

cell death; cell without a nucleus

Question 15

thick skin

Answer 15

has all 5 layers and sweat glands, lacks hair follicles and sebaceous glands

Question 16

where is thick skin found?

Answer 16

on the palms of hands and feet

Question 17

thin skin

Answer 17

has 4 layers only; lacks stratum lucidum, has sweat glands + hair follicles + sebaceous glands

Question 18

where is thin skin found?

Answer 18

on most of the body

Question 19

what type of tissue makes the dermis?

Answer 19

connective

Question 20

two layers of the dermis

Answer 20

papillary and reticular
(papillary is superficial, reticular is deep)

Question 21

what connective tissue makes the papillary layer?

Answer 21

areolar

Question 22

what connective tissue makes the reticular layer?

Answer 22

dense irregular

Question 23

what structure is found in the papillary layer?

Answer 23

dermal papillae

Question 24

what structure(s) are found in the reticular layer?

Answer 24

many; collagen fibers in many directions, hair follicles, sebaceous + sweat glands, nerves and blood vessels

Question 25

cleavage lines

Answer 25

collagen and elastic fibers in skin organized in regions; orient in the direction of stress

Question 26

subcutaneous layer

Answer 26

hypodermis; not part of integument, thickness is influenced by hormones

Question 27

function of subcutaneous layer?

Answer 27

binds skin to underlying structures, provides padding and insulation, energy/lipid storage

Question 28

what connective tissue composes the subcutaneous layer?

Answer 28

areolar and adipose

Question 29

function of integument

Answer 29

protection; physical barrier and protects from UV radiation and harmful chemicals toxins, microbes, etc

Question 30

precursor of vitamin D that sits in the skin

Answer 30

7-dehydrocholesterol

Question 31

what is needed to synthesize vitamin D?

Answer 31

integument, liver, kidney

Question 32

what turns the precursor into vitamin D3?

Answer 32

keratinocytes

Question 33

where does vitamin D3 go to convert to calcidiol?

Answer 33

into the blood, then to the liver

Question 34

how does cacidiol turn into active vitamin D?

Answer 34

calcidiol is transported to kidneys where it turns into calcitriol (active vD)

Question 35

true or false; the integument is selectively permeable, meaning that anything small or nonpolar can be absorbed

Answer 35

true

Question 36

vasoconstriction

Answer 36

vessels diameter decreases; less blood transported through vessel; blood is pulled away from surface to *conserve* heat

Question 37

vasodilation

Answer 37

vessels diameter dilates; more blood transported; blood is closer to body

Question 38

nail matrix

Answer 38

proximal end of nail body; active site of growth

Question 39

lunula

Answer 39

proximal end where stratum basale is thicker and appears white

Question 40

eponychium

Answer 40

the cuticle of the nail