Integument System

Question 1

2 layers of the skin

Answer 1

epidermis & dermis

Question 2

functions of integumentary system

Answer 2

• sensory
• thermoregulation
• metabolism
• sexual signaling

Question 3

cells of the epidermis

Answer 3

keratinocytes
malanocytes
langerhans cells
merkel cells

Question 4

karatinocytes

Answer 4

• most abundant cell of epidermis
• produce keratin
• form epidermal water barrier
• produce vitamin D

Question 5

skin is categorized as ____ or ____

Answer 5

thick or thin

Question 6

thick skin

Answer 6

• found on palms of hands and soles of feet
• 5 layers to epidermis
• subject to most abrasion, hairless

Question 7

thin skin

Answer 7

• found everywhere except palms of hands & soles of feet
• 4 layers to epidermis
• most areas contain hair follicles

Question 8

layers of epidermis

Answer 8

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

Question 9

stratum basale (germinativum)

Answer 9

• single layer of mitotically active cells, rests on basement membrane, allows epidermal renewal of keratinocytes
• keratinocytes undergo keratinization, then apoptosis

Question 10

stratum spinosum

Answer 10

thickest layer, synthesize keratin

Question 11

stratum granulosum

Answer 11

• most superficial layer of still intact nucleated cells
• keratinocytes contain keratohyalin granules (contain keratin)

Question 12

stratum lucidum

Answer 12

• found only in thick skin
• layer of flattened keratinocytes
• cytoplasm contains packed keratin filaments

Question 13

stratum corneum

Answer 13

• anucleate squamous cells (keratinocytes) filled with keratin filament
• extra lipid cell layer as water barrier
• continuously shed and replenished

Question 14

melanocytes produce and secrete ____

Answer 14

melanin

Question 15

melanin

Answer 15

protects against mutagenic affects of UV radiation

Question 16

melanin accumulates in vessels called ____

Answer 16

melanosomes

Question 17

langerhans cells

Answer 17

• dendritic APCs, derived from monocytes
• present antigens to T lymphocytes in nearby lymph nodes
• mostly in stratum spinosum

Question 18

merkel cells

Answer 18

• associated with nerve ending & function as receptors for light touch and texture (tactile sensation)
• abundant in highly sensitive skin (finger tips, bases of hair follicles)

Question 19

surface of dermis has many projections called ____

Answer 19

dermal papillae

Question 20

dermal papillae

Answer 20

fingerlike projections of loose CT into undersurface of epidermis

Question 21

sublayers of dermis

Answer 21

1. papillary layer
2. reticular layer

Question 22

sensory receptors of the skin

Answer 22

1. meissner’s corpuscles
2. pacinian corpuscles

Question 23

function of meissner’s corpuscles

Answer 23

fine, light touch receptors

Question 24

structure of meissner’s corpuscles

Answer 24

• encapsulated nerve ending
• unmyelinated sensory nerve fibers follow a spiral path
• Schwann cells surrounding in helical matter, forming several lamellae

Question 25

location of meissner's corpuscles

Answer 25

- dermal papillae - most numerous in fingertips, palms, soles

Question 26

function of pacinian corpuscles

Answer 26

receptors for course touch, pressure, vibration

Question 27

location of pacinian corpuscles

Answer 27

deeper dermis and hypodermis, especially in fingertips

Question 28

structure of pacinian corpuscles

Answer 28

concentric lamellae of schwann cells surround unmyelinated afferent nerve fiber

Question 29

what are hairs?

Answer 29

elongated keratinized structures that form within hair follicles

Question 30

hair bulb

Answer 30

terminal dilation of hair follicle

Question 31

base of hair bulb is invaginated by a well vascularized tuft of loose CT ____

Answer 31

dermal papillae (sustain the hair follicle)

Question 32

hair root

Answer 32

portion of hair within skin

Question 33

structure of hair root

Answer 33

- inner medulla (less keratinized) - cortex (heavily keratinized) - thin outer cuticle (v heavily keratinized)

Question 34

hair follicle has an outer ____ and an inner ____

Answer 34

CT root sheath epithelial root sheath

Question 35

hair shaft

Answer 35

external portion of hair that extends above epidermis

Question 36

sebaceous glands secrete ____ via ____ secretion

Answer 36

sebum holocrine

Question 37

sebum

Answer 37

- oily lipid substance that coats the hair and skin surface - cells fill with small fat droplets filled with sebum

Question 38

holocrine secretion

Answer 38

cells accumulate product as they mature and enlarge, ending in rupture of cells and release of product

Question 39

arrector pili muscle

Answer 39

- small bundle of smooth muscle attaches to hair follicle - contraction twists hair follicle and elevates hair, forming goosebumps - helps deliver sebum from sebaceous gland into hair follicle

Question 40

pilosebaceous unit

Answer 40

1. hair follicle + hair 2. arrector pili muscle 3. sebaceous gland

Question 41

2 types of sweat glands

Answer 41

eccrine and apocrine

Question 42

function of eccrine sweat glands

Answer 42

produce sweat that is mostly water onto skin surface where evaporation cools the body

Question 43

#eccrine sweat glands _____ cells surround basal aspect of secretory segment

Answer 43

myoepithelial cells

Question 44

function of contraction of myoepithelial cells of eccrine sweat glands

Answer 44

helps release sweat from gland into ducts

Question 45

eccrine sweat glands function via ____ secretion

Answer 45

merocrine

Question 46

apocrine sweat glands contain...

Answer 46

slightly viscous, protein rich products (may develop odor due to bacterial activity)