Ch 6 the Integumentary System

Question 1

what are the functions of the integumentary system

Answer 1

protection, body temperature regulation, cutaneous sensation, metabolic (synthesis of vit D) blood reservoir, excretions

Question 2

epidermis

Answer 2

composed of keratinized stratified squamous epithelium, it contains keratinocytes, melanocytes, Merkel cells, and Langerhans’ cells

Question 3

keratinocytes

Answer 3

produce keratin

Question 4

Langerhans’/dendritic cells

Answer 4

epidermal microphage that helps activate immune system

Question 5

melanocytes

Answer 5

produce brown pigment melanin (UV protection)

Question 6

Merkel cells

Answer 6

touch receptors in association with sensory nerve endings

Question 7

stratum basale

Answer 7

deepest epidermal layer, attached to dermis, single row of youngest keratinocytes, only place you can find melanocytes and Merkel cells

Question 8

stratum spinosum

Answer 8

cells contain weblike system of intermediate filaments attached to desmosomes, melanin granules and Langerhans’ cells are abundant. tight connections created to form strong barrier

Question 9

stratum granulosum

Answer 9

thin, 3-5 cell layers where drastic changes in keratinocyte appearance occurs, glycolipids produced for waterproofing, where cells “toughen up”

Question 10

stratum lucidum

Answer 10

thin transparent band, few rows of dead keratinocytes, present only in thick skin. superficial to stratum granulosum

Question 11

stratum corneum

Answer 11

outermost layer of keratinocytes, 3/4 of epidermis, functions include waterproofing, protection from abrasion and penetration, renders body relatively insensitive to biological, chemical, and physical assaults

Question 12

papillary layer of the dermis

Answer 12

areolar connective tissue, superior surface contains peglike projections called papillae, which contain capillary loops, contain meissner’s corpuscles and free nerve endings for touch

Question 13

reticular layer of dermis

Answer 13

80% of dermis, collagen fibers add strength and resiliency, elastin provides stretch and recoil

Question 14

hypodermis

Answer 14

also subcutaneous later. deep to skin, composed of adipose and areolar connective tissue, not technically skin

Question 15

melanin

Answer 15

yellow to reddish-brownish to black pigment responsible for dark colors. freckle/mole is a local accumulation

Question 16

carotene

Answer 16

yellow to orange, most obvious in palms and soles of feet

Question 17

hemoglobin

Answer 17

reddish pigment responsible for pinkish hue

Question 18

merocrine gland

Answer 18

sweat glands for thermoregulation. secretions formed in vesicles and released by exocytosis, 99% water 1% electrolyte, some nitrogenous waste. 3-4 million in adult body

Question 19

apocrine

Answer 19

sweat gland. modified merocrine, loses portion of cell when sweat is released, sweat contains proteins and lipids bacteria will feast upon. in axillary and pubic regions

Question 20

ceruminous

Answer 20

sweat gland. modified apocrine glands in external ear canal that secrete cerumen

Question 21

mammary

Answer 21

specialized apocrine sweat glands that release milk

Question 22

holocrine

Answer 22

sebaceous gland. cells dividing, as they mature they burst releasing sebum

Question 23

sebum

Answer 23

oily secretion

Question 24

nails

Answer 24

scalelike modification of the epidermis on the distal, dorsal surface

Question 25

hair

Answer 25

filamentous strands of keratinized cell produced by hair follicles. contains hard keratin which is tougher and more durable than keratin on skin. consists of medulla, cortex, and outermost cuticle

Question 26

function of hair

Answer 26

warmth, detect presence of insects, guard scalp against physical trauma, heat loss, sunlight

Question 27

vellus hair

Answer 27

pale fine body hair found in children and adult female

Question 28

terminal hair

Answer 28

course, long hair of eyebrows, scalp, axillary and pubic regions

Question 29

basal cell carcinoma

Answer 29

least malignant and most common, stratum basale cells proliferate and invade dermis and hypodermis, do not metastasize and can usually be cured by surgical excision

Question 30

squamous cell carcinoma

Answer 30

arises from keratinocytes of stratum spinosum, grows rapidly and metastasizes if not removed

Question 31

melanoma

Answer 31

cancer of melanocytes, most dangerous due to highly metastatic and resistant to chemo

Question 32

partial thickness burn

Answer 32

only epidermis, redness swelling and pain

Question 33

full thickness burn

Answer 33

appears grey white, cherry red, black, no edema or pain

Question 34

contracture

Answer 34

when scar tissue is formed preventing movement