Ch. 5

Question 1

what are the two later of the skin

Answer 1

epidermis and dermis

Question 2

what is hypodermis composed of

Answer 2

areolar an adipose tissue

Question 3

what are the 5 important functions of the skin

Answer 3

protection, body temperature regulation, excretion, production of vitamin D, sensory reception

Question 4

what are the 4 main cell types found in the epidermis

Answer 4

keratinocytes, melanocytes, tactile epithelial cells, dendritic cells

Question 5

keratinocytes

Answer 5

located in stratum spinosum produce keratin, fibrous protein

Question 6

melanocytes

Answer 6

found in basal layer; manufacture and secrete pigment

Question 7

tactile epithelial cells

Answer 7

found in basal layer; attached to sensory nerve endings

Question 8

dendritic cells

Answer 8

found in stratum spinosum; part of immune system; macrophage-like

Question 9

what are the layers of the epidermis

Answer 9

stratum basale, stratum spinosum, stratum granulosum, stratum lucid (only in thick skin), stratum corneum

Question 10

what happens in the stratum basale

Answer 10

cells actively divide

Question 11

what does the stratum basal contain

Answer 11

tactile epithelial cells and melanocytes

Question 12

what does the stratum spinosum contain

Answer 12

thick bundles of intermediate filaments, dendritic cells

Question 13

what does stratum granulosum consist of

Answer 13

few layers of keratinocytes

Question 14

what do keratinocytes contain

Answer 14

keratohyaline granules- help form keratin, lamellar granules-contain waterproofing glycolipid

Question 15

descrie stratum lucidum

Answer 15

occurs only in thick skin (palms and soles), composed of a few rows of flat, dead keratinocytes

Question 16

describe the stratum corneum

Answer 16

thick layers of dead keratinocytes and thickened plasma membranes, protects skin against abrasion and penetration

Question 17

what are the two layers of the dermis

Answer 17

papillary dermis (includes dermal papillae) and reticular dermis (deeper layer)

Question 18

describe the papillary dermis

Answer 18

includes dermal papillae, increase surface area for exchange of gases, nutrients, and wastes

Question 19

what are epidermal ridges (friction ridges)

Answer 19

elevation of dermal ridges, AKA fingerprints

Question 20

purpose of epidermal ridges

Answer 20

increases gripping ability of hands and feet

Question 21

cleavage lines

Answer 21

separation b/t collagen fibers

Question 22

flexure lines

Answer 22

deep creases in palms, wrists, soles, finger, and toes

Question 23

what are the two types of vascular plexuses found in the reticular dermis

Answer 23

dermal plexus, and sub papillary plexus

Question 24

what type of tissue is in the hypodermis

Answer 24

areolar and adipose connective tissue

Question 25

function of hypodermis

Answer 25

anchors skin to underlying structures, helps insulate body

Question 26

what is another name for the hypodermis

Answer 26

superficial fascia

Question 27

name the 3 pigments that contribute to skin color

Answer 27

melanin, carotene, hemoglobin

Question 28

what is melanin made of

Answer 28

made from tyrosine

Question 29

carotene

Answer 29

yellowish pigment from carrots and tomatoes

Question 30

hemoglobin

Answer 30

caucasian skin contains little melanin, allows crimson color of blood to show though

Question 31

nails

Answer 31

scalelike modifications of epidermis make of hard keratin

Question 32

list the parts of the nail

Answer 32

free edge, body, root, nail folds, eponychium

Question 33

describe hair

Answer 33

flexible strand of dead, keratinized cells

Question 34

what are the parts of hair

Answer 34

root (embedded in skin), and shaft (projections above skin's surface)

Question 35

name the 3 concentric layers of keratinized cells hair contains

Answer 35

medulla (center core), cortex (surrounds medulla), and cuticle (outermost layer)

Question 36

hair follicles

Answer 36

extend from epidermis into dermis

Question 37

hair bulb

Answer 37

deep, expanded end of he hair follicle

Question 38

root plexus

Answer 38

knot of sensory nerves around hair bulb

Question 39

arrestor pili muscle

Answer 39

bundle of smooth muscle, hair stands erect when arrector pili contracts

Question 40

villus hairs

Answer 40

body hairs of women and children

Question 41

terminal hairs

Answer 41

hair of scalp, axillary, and pubic area (at puberty)

Question 42

sebaceous glands are found one entire body except

Answer 42

palms and soles

Question 43

function of sebum

Answer 43

collects dirt; softens and lubricates hair and skin

Question 44

what is sweat

Answer 44

a blood filtrate, 99% water w/ some salts

Question 45

what are the two types o sweat glands

Answer 45

eccrine gland (merocrine) and apocrine gland

Question 46

what do eccrine gland (merocrine) produce

Answer 46

produce true sweat

Question 47

where are apocrine glands confined

Answer 47

axillary, anal, and genital areas

Question 48

what do procaine glands produce

Answer 48

special kind of sweat, musky odor attracts mate; signal info. about person's immune system etc.

Question 49

name 2 modified apocrine lgands

Answer 49

ceruminous glands and mammary glands

Question 50

describe first degree burns

Answer 50

only upper epidermis is damaged

Question 51

describe second degree burns

Answer 51

upper part of dermis is also damaged; blisters appear, skin heals w/ little scarring

Question 52

describe third degree burns

Answer 52

consumes thickens of skin, area appears white, red, or blackened

Question 53

what are the 3 types of skin cancer

Answer 53

basal cell carcinoma, squamous cell carcinoma, and melanoma

Question 54

what type of skin cancer is the least malignant and most common

Answer 54

basal cell carcinoma

Question 55

what is the most dangerous type of skin cancer

Answer 55

melanoma

Question 56

where does the epidermis develop from

Answer 56

embryonic ectoderm

Question 57

where does the dermis and hypodermis develop from

Answer 57

mesoderm

Question 58

what do melanocytes develop from

Answer 58

neural crest cells