A&p Midterm Ch. 05

Front 1

integumentary system

Back 1

system that forms the external body covering, protects deeper tissues, and houses sensory receptors and sweat and oil glands; skin, hair, nails

Front 2

1. epidermis
2. dermis

Back 2

2 layers of the skin:

Hint 2

Front 3

hypodermis (superficial fascia)

Back 3

subcutaneous tissue just deep to the skin, and superficial to connective tissue; mainly consists of adipose tissue

Hint 3

Front 4

1. stores fat
2. anchors skin
3. absorbs shock
4. insulates (reduces heat loss)

Back 4

4 functions of the hypodermis

Front 5

epidermis

Back 5

keratinized superficial layer of the skin; avascular, receives nutrients by diffusion

Hint 5

Front 6

keratinized stratified squamous epithelium

Back 6

the type of epithelium that forms the epidermis

Front 7

1. keratinocytes
2. melanocytes
3. Langerhans cells
4. Merkel cells

Back 7

4 cell types found in the epidermis

Hint 7

Front 8

keratinocytes

Back 8

epidermal cells that produce keratin; most common

Front 9

keratin

Back 9

the fibrous protein that helps give the epidermis its protective properties

Front 10

desmosomes

Back 10

tightly connect keratinocytes

Front 11

callus

Back 11

a thickening of the epidermis caused by persistent friction

Front 12

melanocytes

Back 12

spider–shaped epithelial cells that synthesize the pigment melanin upon sunlight stimulation

Front 13

melanosomes

Back 13

melanin granules that accumulate on the upper side of keratinocytes, protecting DNA from UV rays

Front 14

dendritic cells (Langerhans cells)

Back 14

star–shaped macrophages that ingest foreign substances and play a key role in immunity; arise in bone marrow and migrate to the epidermis

Front 15

Merkel cells (tactile cells)

Back 15

cells that combine with nerve endings to form Merkel discs (tactile discs); present at the epidermal–dermal junction

Front 16

Merkel discs (tactile discs)

Back 16

function as sensory receptors for touch; composed of tactile cells (Merkel cells) and nerve endings

Front 17

thick skin

Back 17

skin covering areas subject to abrasion; palms, fingertips, soles of the feet

Front 18

1. stratum basale
2. stratum spinosum
3. stratum granulosum
4. stratum lucidum
5. stratum corneum

Back 18

5 layers (strata) of the epidermis

Hint 18

Front 19

stratum basale

Back 19

epidermal layer attached to the underlying dermis; single layer of stem cells (young keratinocytes), melanocytes, and Merkel cells

Hint 19

Front 20

stratum germinativum

Back 20

alternate name for the stratum basale, meaning "germinating layer"

Front 21

stratum spinosum

Back 21

epidermal layer containing cells with weblike systems of intermediate filaments that attach to desmosomes; houses keratinocytes, melanin granules, and dendritic cells

Hint 21

Front 22

stratum granulosum

Back 22

epidermal layer where keratinization begins; houses keratohyaline granules and lamellar granules

Hint 22

Front 23

keratinization

Back 23

process of keratinocytes filling with the fibrous protein keratin; begins in stratum granulosum

Front 24

1. keratohyaline
2. lamellar

Back 24

2 types of granules found in the stratum granulosum

Front 25

keratohyaline granules

Back 25

granules that help to form keratin in the upper layers

Front 26

lamellar granules

Back 26

granules that contain a water–resistant glycolipid that slows water loss

Front 27

stratum lucidum

Back 27

epidermal layer housing two to three rows of dead keratinocytes and tonofilaments; only found in thick skin

Front 28

tonofilaments

Back 28

large arrays of special intermediate filaments caused by keratohyaline granules clinging to keratin filaments in the cells

Front 29

stratum corneum

Back 29

outermost epidermal layer consisting of 20 to 30 layers of dead cells; protects and waterproofs

Hint 29

Front 30

cornified cells (horny cells)

Back 30

the shingle–like cell remnants of the stratum corneum

Front 31

dermis

Back 31

the strong, flexible connective tissue layer of the skin; well vascularized

Hint 31

Front 32

1. papillary
2. reticular

Back 32

2 layers of the dermis

Hint 32

Front 33

papillary layer

Back 33

thin superficial layer of the dermis; houses freely wandering defensive cells and small blood vessels; 20% of dermis thickness

Hint 33

Front 34

dermal papillae

Back 34

projections from the papillary layer of the dermis containing capillary loops, nerve endings, and fine touch receptors (Meissner's corpuscles)

Front 35

free nerve endings

Back 35

pain receptors located in the papillary layer of the dermis

Front 36

Meissner's corpuscles (tactile corpuscles)

Back 36

fine touch receptors located in the papillary layer of the dermis

Front 37

friction ridges

Back 37

skin ridges that enhance grip ability, and help amplify vibrations for touch receptors

Front 38

fingerprints

Back 38

caused by sweat pores opening along friction ridges; genetically determined and unique for every person

Front 39

reticular layer

Back 39

deeper dermal layer consisting of the cutaneous plexus and pockets of adipose cells and collagen fibers; 80% of dermis thickness

Hint 39

Front 40

Pacinian corpuscles

Back 40

deep pressure receptors of the reticular layer of the dermis

Front 41

cutaneous plexus

Back 41

the network of blood vessels that nourishes the reticular layer of the dermis

Front 42

cleavage lines (tension lines)

Back 42

formed by less dense regions of dermal collagen fibers running parallel to the skin surface

Front 43

flexure lines

Back 43

dermal folds that occur near joints, where the dermis is tightly secured to deeper structures

Front 44

1. friction ridges
2. cleavage (tension) lines
3. flexure lines

Back 44

3 dermal modifications resulting in characteristic skin markings

Front 45

striae (stretch marks)

Back 45

extreme stretching of the skin

Front 46

blisters

Back 46

fluid–filled pockets, caused by trauma, that separate the epidermal and dermal layers

Front 47

1. melanin
2. carotene
3. hemoglobin

Back 47

3 pigments contributing to skin color

Front 48

melanin

Back 48

pigment that helps protect DNA from UV radiation, causing skin to darken; reddish yellow to brownish black

Front 49

sunspots

Back 49

small circular white spots on the skin caused by a fungal infection, not sun exposure

Front 50

carotene

Back 50

yellow/orange pigment that accumulates in the stratum corneum, converted to vitamin A (helps with vision); found in certain plants (ex. carrots)

Front 51

hemoglobin

Back 51

crimson–colored oxygenated pigment in red blood cells

Front 52

cyanosis

Back 52

blue skin tone caused by poorly oxygenated blood; ex. heart failure, respiratory disorders

Front 53

erythema

Back 53

red skin tone caused by blushing, fever, hypertension, inflammation, or allergy

Front 54

pallor

Back 54

pale skin due to emotional stress, fear, low blood pressure, etc.

Front 55

jaundice

Back 55

abnormal yellow skin tone usually caused by a liver disorder (accumulation of bile pigments)

Front 56

bronzing

Back 56

bronze skin tone caused by Addison's disease (lack of steroid hormones) or pituitary gland tumors that secrete melanocyte–stimulating hormone

Front 57

bruises

Back 57

black and blue marks caused by escaped and clotted blood beneath the skin (hematomas)

Front 58

1. hair
2. nails
3. sweat glands
4. oil glands

Back 58

4 skin appendages that originate in the epidermis and grow down into the dermis

Front 59

1. more durable

2. does not flake off

Back 59

2 advantages of hard keratin over soft keratin

Front 60

hairs (pili)

Back 60

flexible strands of hard, dead keratinocytes

Front 61

1. protection
2. filtration
3. sensory
4. warmth

Back 61

4 functions of hair

Front 62

1. shaft
2. root

Back 62

2 main regions of a hair

Front 63

shaft

Back 63

the portion of a hair where keratinization is complete

Front 64

root

Back 64

the portion of a hair where keratinization is still ongoing

Hint 64

Front 65

1. medulla
2. cortex
3. cuticle

Back 65

3 concentric layers of a hair

Hint 65

Front 66

medulla

Back 66

innermost layer of a hair consisting of large cells and air spaces; absent in fine hair

Hint 66

Front 67

cortex

Back 67

bulky layer of hair consisting of several layers of flattened cells

Hint 67

Front 68

cuticle

Back 68

outer layer of hair consisting of overlapping cells like shingles on a roof

Hint 68

Front 69

hair follicle

Back 69

part of a hair buried in the dermis that produces the hair; forms in the epidermis

Front 70

hair bulb

Back 70

the expanded deep end of a hair follicle

Hint 70

Front 71

hair follicle receptor (root hair plexus)

Back 71

a knot of sensory nerve endings wrapped around each hair bulb; stimulated by bending the hair

Hint 71

Front 72

hair papilla

Back 72

nipple–like protrusion into the hair bulb containing capillaries that supply nutrients to growing hair and signals it to grow

Hint 72

Front 73

hair matrix

Back 73

the actively dividing area of the hair bulb that produces the hair by pushing up dead, keratinized cells

Hint 73

Front 74

1. peripheral connective tissue (fibrous sheath)
2. glassy membrane
3. epithelial root sheath

Back 74

3 outer layers of the hair follicle wall

Hint 74

Front 75

arrector pili

Back 75

a bundle of smooth muscle cells that pulls a hair follicle upright, forcing sebum out

Front 76

vellus hair

Back 76

pale, fine hair; body hair of children and females

Front 77

terminal hair

Back 77

coarse, long hair; eyebrows and scalp, axillary and pubic regions, face and chest (males)

Front 78

hirsutism

Back 78

excessive hairiness, caused by an adrenal gland or ovarian tumor secreting high levels of androgens

Front 79

alopecia

Back 79

baldness as a result of age; hairs are shed faster than they're replaced

Front 80

male pattern baldness

Back 80

most common type of true baldness; follicular growth cycles become so short that hairs shed before they emerge

Front 81

alopecia areata

Back 81

rare condition in which the immune system attacks the follicles and hair falls out in patches

Front 82

nail

Back 82

clear, protective covering on the fingers and toes; a scalelike modification of the epidermis

Hint 82

Front 83

1. protection
2. tools

Back 83

2 functions of the nails

Front 84

1. free edge
2. nail body
3. root

Back 84

3 main parts of a nail

Hint 84

Front 85

nail bed

Back 85

the deeper layers of the epidermis extending beneath the nail

Hint 85

Front 86

nail matrix

Back 86

the thickened proximal portion of the nailbed, responsible for nail growth

Hint 86

Front 87

nail folds (epinychium)

Back 87

skin folds overlapping the proximal and lateral borders of a nail

Hint 87

Front 88

cuticle

Back 88

the proximal nail fold that projects onto the body

Hint 88

Front 89

hyponychium

Back 89

the thickened region beneath the free edge of a nail

Hint 89

Front 90

sweat glands (sudiferous glands)

Back 90

merocrine glands distributed over the skin responsible for perspiration; up to 3 million per person

Hint 90

Front 91

1. eccrine
2. apocrine

Back 91

2 types of sweat glands

Front 92

eccrine sweat glands (merocrine sweat glands)

Back 92

simple tubular merocrine sweat glands abundant on the palms, soles, and forehead

Front 93

sweat

Back 93

acidic eccrine gland secretion

Front 94

dermcidin

Back 94

microbe–killing peptide found in sweat

Front 95

apocrine sweat glands

Back 95

scent sweat glands confined to the axillary and genital regions, add fatty substances and proteins to sweat; "sexual scent glands" activated during adolescence; approx. 2000

Front 96

ceruminous glands

Back 96

modified apocrine glands lining the external ear; produce cerumen (earwax)

Front 97

mammary glands

Back 97

specialized apocrine glands that secrete milk

Front 98

sebaceous glands (oil glands)

Back 98

simple branched alveolar holocrine glands that secrete sebum wherever hair is found; activated during adolescence

Hint 98

Front 99

sebum

Back 99

an oily, bactericidal secretion that softens hair and skin

Front 100

acne

Back 100

an inflammation of the sebaceous glands caused by bacterial infection

Front 101

1. protection
2. temperature
3. sensation
4. metabolism
5. blood reservoir
6. excretion

Back 101

6 functions of the integumentary system

Front 102

1. chemical
2. physical
3. biological

Back 102

3 types of barriers that protect the skin

Front 103

acid mantle

Back 103

the low pH of skin secretions

Front 104

defensins

Back 104

antibodies secreted by the skin that punch holes in bacteria

Front 105

cathelicidins

Back 105

protective peptides released by damaged skin that prevent infection

Front 106

1. dendritic cells (epidermis)
2. macrophages (dermis)

Back 106

2 types of biological barriers in the skin

Front 107

insensible perspiration

Back 107

routine and unnoticeable sweat; occurs in temperatures below 90° F

Front 108

sensible perspiration

Back 108

visible sweat; occurs in temperatures above 90° F

Front 109

cutaneous sensory receptors

Back 109

exteroreceptors responsible for cutaneous sensation

Front 110

exteroreceptors

Back 110

receptors that respond to stimuli arising outside the body

Front 111

1. Merkel cells (epidermis)
2. Meissner corpuscles (dermal papillae)

3. free nerve endings (dermal papillae)
4. Pacinian corpuscles (dermis/hypodermis)
5. root hair plexuses (dermis)

Back 111

5 types of cutaneous sensory receptors

Front 112

5%

Back 112

% of blood held in the dermal vascular supply

Front 113

1. bacterial
2. viral
3. fungal

Back 113

3 types of skin infections

Front 114

psoriasis

Back 114

characterized by reddened epidermal lesions and white patches (scales)

Front 115

1. basal cell carcinoma
2. squamous cell carcinoma
3. melanoma

Back 115

3 major forms of skin cancer

Hint 115

Front 116

basal cell carcinoma

Back 116

least malignant and most common skin cancer, 80% of cases; shiny, dome–shaped nodules arising from the stratum basale invade the dermis and hypodermis

Hint 116

Front 117

squamous cell carcinoma

Back 117

second most common skin cancer; scaly, reddened papule arising from the keratinocytes of the stratum spinosum

Hint 117

Front 118

melanoma

Back 118

the most dangerous skin cancer, 2–3% of cases; spreading brown to black patch arising from melanocytes

Hint 118

Front 119

Asymmetry
Border irregularity
Color
Diameter
Elevation

Back 119

ABCDE rule for recognizing melanoma

Front 120

burn

Back 120

tissue damage inflicted by intense heat, electricity, radiation, or chemicals; denatures proteins and kills cells in the affected areas

Front 121

1. loss of body fluids (immediate)

2. loss of proteins

3. infection

Back 121

3 dangers of burns

Front 122

infection

Back 122

leading cause of death in burn patients

Front 123

first–degree burn

Back 123

burn damaging only the epidermis; redness, swelling, pain; ex. sunburn

Front 124

second–degree burn

Back 124

burn damaging the epidermis and upper dermis; swelling, redness, blisters

Front 125

partial–thickness burns

Back 125

used to describe first– and second–degree burns

Front 126

third–degree burn

Back 126

burn affecting the entire thickness of the skin; full–thickness burn, requires skin graft

Front 127

ectoderm

Back 127

the primary germ layer that develops into the epidermis

Front 128

mesoderm

Back 128

the primary germ layer originating the dermis and hypodermis

Front 129

lanugo coat

Back 129

the coat of delicate, colorless hairs covering a fetus

Front 130

vernix caseosa

Back 130

white substance that protects the fetus's skin when a baby is born

Front 131

dermatitis

Back 131

scaling and various kinds of skin inflammation often occurring from age 40 and beyond

Front 132

loop

Back 132

Hint 132

Front 133

whorl

Back 133

Hint 133

Front 134

arch

Back 134

Hint 134