Integumentary System

Question 1

Integument

Answer 1

skin

Question 2

Dermatology

Answer 2

study of skin

Question 3

Epidermis

Answer 3

keratinized, stratified squamous epithelium, superficial

Question 4

Dermis

Answer 4

deeper layer, primarily dense irregular CT (proper CT);
2 layers:
papillary
deeper reticular

Question 5

Hypodermis (subcutaneous layer)

Answer 5

deep to dermis; layer of areolar and adipose CT; not apart of integumentary system

Question 6

Layers of epidermis (deep to stratified)

Answer 6

Stratum basale
Stratum spinosum
Stratum granulosum
Stratum lucidum
Stratum corneum

Question 7

Stratum basale (basal layer)

Answer 7

deepest epidermal layer; germinative layer; single layer of cells;
Cell Types:
Keratinocytes (living cells)
Melanocytes
Tactile cells

Question 8

Keratinocytes

Answer 8

most abundant cells in epidermis, divide to regenerate new cells, replace old cells shed at surface; synthesizing of keratin

Question 9

Keratin

Answer 9

protein that strengthens epidermis and makes skin almost waterproof

Question 10

Melanocytes

Answer 10

scattered among keratinocytes; produces and stores melanin in response to UV light; transfer pigment granules (melanosomes) into keratinocytes; shields nuclear DNA from UV radiation

Question 11

melanosomes

Answer 11

packaged melanin; the pigment accumulates around nucleus of keratinocytes

Question 12

Tactile Cells (merkel cells)

Answer 12

few; sensitive to touch; when compressed release chemicals to stimulate sensory nerve endings

Question 13

Stratum spinosum

Answer 13

several layers of keratinocytes; daughter cells from stratum basale

Question 14

Epidermal Dendritic cells (langerhans cells)

Answer 14

branching extensions; initiate immune response; phagocytosis cells; responsive to pathogens and epidermal cancer cells

Question 15

Stratum granulosum

Answer 15

3-5 layers of keratinocytes; beginning of keratinization, producing keratin but not enough that it is still alive, nucleus and organelles start to disintegrate

Question 16

Stratum lucidum

Answer 16

2-3 layers, translucent; only on thick skin on palms and soles; transparent because of intermediate product in maturation of keratin; composed of dead skin cells

Question 17

Stratum corneum

Answer 17

most superficial, 20-30 layers of dead skin; cells are anucleste and tightly packed; dry surface protects and is unsuitable for microorganism growth; about 2 weeks then shed

Question 18

anucleate

Answer 18

without a nucleus

Question 19

Migration of keratinocytes

Answer 19

originate from stem stem cells in stratum basale
migrates through strata to stratum corneum (2 weeks)
undergoes structural changes

Question 20

Thick Skin

Answer 20

palm of hands and soles of feet; all 5 layers of epidermal strata; sweat glands; no hair follicles or sebaceous glands

Question 21

Thin Skin

Answer 21

covers most of body; lacks stratum lucidum; contains sweat glands, hair follicles, and sebaceous glands

Question 22

Papillary layer

Answer 22

superficial region; areolar CT