Integumentary System

Question 1

Integument comprised of (5)

Answer 1

Skin, sweat glands, sebaceous glands, hair, nails

Question 2

Skin functions (5)

Answer 2

reception, protection, regulation of body temperature, excretion, absorption

Question 3

Mechanoreceptor types (4)

Answer 3

merkel disc, meissner’s corpuscle, pacinian corpuscle, ruffini organ

Question 4

Epidermis

Answer 4

-4-5 cell layers constantly shed and replaced
-produces keratin, pigment, and immune cells
-no dedicated blood supply
-derived from ectroderm
free nerve endings

Question 5

Dermis

Answer 5

• CT containing collagen and elastin fibers
• Contains blood vessels, nerve endings, hair follicles and glands
• major role in formation and adhesion of epithelial cells
• derived from mesoderm

Question 6

Hypodermis (superficial fascia)

Answer 6

loost CT with adipose cells

Question 7

Rete apparatus

Answer 7

interface between epidermis and dermis made of raised ridges of dermis (dermal ridges/papillae) and invaginations of epidermis (epidermal ridges)

Question 8

Cell type in epidermis

Answer 8

stratified squamous keratinized epithelium

Question 9

4 cell populations in epidermis

Answer 9

keratinocytes, melanocytes, langerhans cells, merkel cells

Question 10

Five zones of keratinocytes

Answer 10

stratum basale (germinativum), stratum spinosum, stratum granulosum, stratum lucidum (not always present), stratum corneum

Question 11

Keratinocytes produce

Answer 11

keratin, lipids, lipoproteins, lamellar bodies

Two types of granules:

• keratohyalin granules: not membrane bound, contain keratin filaments, toughen skin
• lamellar bodies

Question 12

largest population of cells in skin

Answer 12

keratinocytes

Question 13

Cytomorphosis

Answer 13

changes that cells undergo during development. Occurs at night in keratinocytes.

Question 14

desmosomes

Answer 14

-on lateral cell membrane of keratinocytes attaching stratum basale cells to each other and to cells of stratum spinosum

Question 15

hemidesmosomes

Answer 15

basally located. Attach basal cell membrane to basal lamina

Question 16

Stratum corneum

Answer 16

cytoplasm of cells replaced by keratin

Question 17

stratum granulosum

Answer 17

substance from keratohyalin granules combines with the tonofibrils converting them to keratin

Question 18

upper stratum spinosum

Answer 18

cells begin to produce keratohyalin granules

Question 19

lower stratum spinosum

Answer 19

tonofilaments merge into bundles called tonofibrils

Question 20

stratum basale

Answer 20

cells begin synthesizing intermediate filaments called tonofilaments

Question 21

lamellar bodies

Answer 21

AKA membrane coating granules

• membrane bound
• contain glycophospholipid
• waterproof the skin

Question 22

waterproofing of skin

Answer 22

• lipids make hydrophobic barrier
• in stratum granulosum lipid contents of lamellar bodies are extruded into the intercellular spaces
• keratinocytes also produce lamellar bodies

Question 23

melanocytes

Answer 23

in stratum basale. Contain tyrosinase

Question 24

tyrosinase pathway

Answer 24

• tyrosinase transported into cell and converted to melanin by tyrosinase
• melanin transferred to keratinocytes via melanosomes to keratinocytes

Question 25

Langerhans cells (dendritic cells)

Answer 25

- contain birbeck granules (unknown function) | - phagocytosis and antigen presenting cells

Question 26

Merkel cells

Answer 26

- respond to light touch - associated with sensory nerves which traverse basal lamina of the epidermis - always found in rete apparatus at lowest point of epidermis

Question 27

Papillary layer of dermis

Answer 27

- type III collagen - elastic fibers - anchoring fibrils (VII) - capillary loops - CT cells

Question 28

Reticular layer of dermis

Answer 28

- type I collagen - elastic fibers - sweat glands - sebaceous (oil) glands - hair follicles - smooth muscle cells

Question 29

Glands in reticular layer of dermis

Answer 29

- Sweat glands: eccrine and apocrine | - Sebaceous glands

Question 30

Eccrine sweat glands

Answer 30

-merocrine secretion (excretion via exocytosis)

Question 31

myoepithelial cells

Answer 31

- have characteristics of smooth muscle but of epithelial origin - wrap around secretory units (acini) and some small ducts - contractions help excretions from gland

Question 32

apocrine sweat gland

Answer 32

- found only in axilla (arm pit), areola of nipple and anal region - ducts of apocrine glands open into canals of hair follicles

Question 33

Sebaceous glands

Answer 33

- NOT found in palms of hands, soles of feet, and sides of feet - in dermis - secretes sebum - associated with hair follicles

Question 34

sebum

Answer 34

wax like, oily mix of cholesterol, triglycerides, etc. From sebaceous glands

Question 35

pacinian corpuscle

Answer 35

- deep pressure/ vibration receptor | - in dermis

Question 36

ruffini organ

Answer 36

- stretch receptor | - in dermis

Question 37

meissener corpuscle

Answer 37

- light touch receptor | - in dermis

Question 38

merkel disks

Answer 38

- light touch receptor | - in epidermis

Question 39

free nerve endings

Answer 39

- pain receptor | - in epidermis