B6-025 Skin Development

Question 1

acts as a storage center for lipids and water; shock absorber

Answer 1

hypodermis

Question 2

skin movements are limited by [2]

Answer 2

retinacula cutis fibers
fasciae

Question 3

allows dermis and fasciae to glide on each other

Answer 3

retinucula cutis fibers

Question 4

melanocytes derive from

Answer 4

neural crest

Question 5

sensory receptors in skin derive from

Answer 5

neural crest

Question 6

mesenchyme/connective tissue of skin in the cranial region derives from

Answer 6

neural crest

Question 7

what layer of the skin arises from non-neural ectoderm?

Answer 7

epidermis

Question 8

what layer of skin arises from neural ectoderm?

Answer 8

dermis and hypodermis in head and neck

Question 9

temporary protective layer cast off into amniotic fluid later in development

Answer 9

periderm

Question 10

5 layers of epidermis

Answer 10

stratum corneum
stratum lucidum (thick skin)
stratum granulosum
stratum spinosum
stratum basale

Question 11

langerhans cells and spinous cells are found in which layer of epidermis?

Answer 11

stratum spinosum

Question 12

melanocytes reside in what layer of epidermis?

Answer 12

stratum basale

Question 13

what layer of skin is responsible for fingerprints?

Answer 13

stratum basale

Question 14

abundant tonofibrils with desmosomes

Answer 14

stratum spinosum

Question 15

caused by excessive keratinization of the skin

Answer 15

harlequin ichthyosis

Question 16

globally reduced or absent pigmentation

Answer 16

albinism

Question 17

loss of melanocytes in patches of skin, hair, and oral mucosa due to autoimmune disorder

Answer 17

vitiligo

Question 18

patchy absence of hair pigment

Answer 18

piebaldism

Question 19

patches of white skin and hair
irises of eyes are different colors
deafness

Answer 19

Waardenburg syndrome

Question 20

antigen presenting immune cells of the epidermis

Answer 20

Langerhans cells

Question 21

where in the skin do blood vessels lie?

Answer 21

dermis

Question 22

papillary layer of the dermis forms […] to increase the surface area

Answer 22

dermal papillae

Question 23

what layer of skin contains roots of hair, hair bulbs, and hair papillae?

Answer 23

reticular layer of the dermis

Question 24

create Langers lines, which is imperative to wound healing

Answer 24

reticular layer of dermis

Question 25

epidermal appendages arise from the [...] and migrate down into the dermis

Answer 25

ectoderm

Question 26

how does a hair follicle develop?

Answer 26

1. epidermal proliferation from stratum basale form and penetrate dermis 2. terminal end (hair bud) invaginates to form hair papilla 3. hair papilla fills with mesoderm (allows vessels and nerve endings to develop)

Question 27

the mesenchyme surrounding an epithelial hair sheath forms [2]

Answer 27

dermal root sheath arrector pili muscle

Question 28

hair grows via continuous proliferation of epithelial cells at the [...] that pushes the hair up to the surface

Answer 28

follicle base/hair bulb

Question 29

do not lose cytoplasm in the secretions

Answer 29

eccrine

Question 30

release some cytoplasm in secretions

Answer 30

apocrine

Question 31

what type of sweat glands form in the axilla?

Answer 31

apocrine

Question 32

secretions from the [...] gland help form the vernix caseosa

Answer 32

sebaceous

Question 33

persistence of parts of the mammary line causes

Answer 33

polythelia (accessory nipple)

Question 34

polymastia occurs when the remnant of the mammary line develops into a

Answer 34

complete breast

Question 35

when lactiferous ducts open into an epithelial pit that failed to evert, the result is

Answer 35

inverted nipples

Question 36

epidermal thickenings appear at the tips of digits and form

Answer 36

nail fields

Question 37

nail fields grow proximally, forming a

Answer 37

nail root

Question 38

superficial fascia layer that attaches skin to the underlying deep fascia of bone/muscle

Answer 38

hypodermis

Question 39

congenital absence of skin, generally isolated lesions on scalp

Answer 39

cutis aplasia

Question 40

skin is inelastic and hangs loosely due to decrease in elastin

Answer 40

cutis laxa

Question 41

fragile, bruisable skin that heals with peculiar scars

Answer 41

Ehlers-Danlos syndrome

Question 42

caused by a mutation in collagen causing altered collagen synthesis

Answer 42

Ehlers-Danlos

Question 43

autosomal dominant disease of keratin that causes skin to be fragile and blister easily

Answer 43

epidermolysis bullosa

Question 44

the connective tissue of the dermis of the skin of the back is derived from

Answer 44

dermatome region of somite

Question 45

gives rise to some muscles of the back, body wall, and limbs

Answer 45

myotome

Question 46

gives rise to vertebrae, ribs and rib cartilage

Answer 46

sclerotome

Question 47

gives rise to cardiac muscle, smooth muscle, and blood vessels

Answer 47

lateral plate mesoderm

Question 48

gives rise to dermis of back

Answer 48

dermatome

Question 49

gives rise to mammary glands

Answer 49

epidermis

Question 50

mammary glands begin as [...] which give rise to [...]

Answer 50

epithelial sprouts epithelial buds

Question 51

create a physical barrier against pathogens and produce proinflammatory chemokines

Answer 51

keratinocytes

Question 52

create pigment that protect against the sun's harmful rays

Answer 52

melanocytes

Question 53

mechanoreceptors of the skin

Answer 53

merkel cells

Question 54

hair roots and the hair follicle are located in the [...] layer

Answer 54

dermal reticular

Question 55

nails derive from the

Answer 55

ectoderm

Question 56

nail fields give rise to the

Answer 56

nail roots

Question 57

nail fields form at

Answer 57

distal tips of digits then form nail roots

Question 58

keratinocytes originate in the [...] and migrate throughout the epidermis

Answer 58

stratum basale

Question 59

increase the surface area of the dermis and maintain contact with the overlying epidermis prevent blistering

Answer 59

dermal papillae