skin

Question 1

____ is the body’s largest organ

Answer 1

skin

Question 2

____ is a vital, complex, diverse, and extensive organ

Answer 2

skin

Question 3

Skin consists of 2 main layers:

Answer 3

• Epidermis

- Dermis

Question 4

Superficial epithelial layer

Answer 4

Epidermis

Question 5

Deep vascular connective tissue layer

Answer 5

Dermis

Question 6

flat organ classified as a membrane

Answer 6

cutaneous membrane

Question 7

system consisting of skin and appendages (hair, glands, nails, etc)

Answer 7

Integumentary system

Question 8

Type of skin that covers most of our body surface, everywhere except palms of hands & soles of feet

Answer 8

Thin skin

Question 9

Type of skin that does not contain hair, found on soles of our feet and palms of our hands. Friction ridges form fingerprints

Answer 9

Thick skin

Question 10

____ ____ are created by the projections of the epidermis that lock into the papillary dermis (upward projections of the dermis)

Answer 10

Friction ridges

Question 11

Most superficial layer of skin composed of several different types of epithelial cells

Answer 11

Epidermis

Question 12

Epidermis consists of the following 4 types of epithelial cells:

Answer 12

• keratinocytes
• melanocytes
• dendritic cells
• tactile epithelial cells (merkel cells)

Question 13

Tough fibrous protein that protects the epidermis from mechanical and shearing forces

Answer 13

keratin

Question 14

_____ constitutes over 90% of cells present in epidermis

Answer 14

keratinocytes

Question 15

Once keratinocytes have migrated to the outer most layer and flattened out, they are sometimes called _____.

Answer 15

corneocytes

Question 16

__cytes do not migrate.

Answer 16

melanocytes

Question 17

type of cell in epidermis that makes granules of pigment called melanin

Answer 17

Melanocytes

Question 18

pigment that migrates around nucleus of specialized cell to shield DNA from UV radiation by reducing the amount of UV that can penetrate into deeper layers of skin

Answer 18

melanin

Question 19

type of cell in the epidermis that are branched and play a role in the immune response

Answer 19

Dendritic cells

Question 20

Type of cell in the epidermis located in the deepest layer of the epidermis near sensory nerve endings and serve as light touch receptors

Answer 20

Tactile (Merkel) cells

Question 21

5 layers or strata of the epidermis are:

Answer 21

Superficial to deep:

• stratum Corneum
• stratum Lucidem
• stratum Granulosum
• stratum Spinosum
• stratum Basale

Come, Let’s Get Sun Burn!

Question 22

Type of distinct epidermis layer only found in thick skin

Answer 22

stratum lucidum

Question 23

Base layer of the epidermis attached to the basement membrane via Rete Pegs and consist of 1 layer of columnar cells

Answer 23

stratum basale

Question 24

downward projections into the papillary dermis

Answer 24

Rete Pegs

Question 25

spiny layer of the epidermis where cells are arranged in 8 to 10 layers of irregularly shaped cells. These cells are rich in RNA

Answer 25

stratum spinosum

Question 26

granular layer of the epidermis that is 3-5 layers thick. Keratinocytes begin keratin formation here

Answer 26

stratum granulosum

Question 27

release a lipid rich fluid that acts as a water-repellent sealant to reduce water and particle loss/entry

Answer 27

lamellar granules

Question 28

cells start degeneration, getting further away from the blood supply in this epidermis layer

Answer 28

stratum granulosum

Question 29

programmed cell death

Answer 29

apoptosis

Question 30

clear layer of the epidermis ONLY present in thick skin. few layers thick of flattened, dead keratinocytes

Answer 30

stratum lucidum

Question 31

AKA "horny" layer of the epidermis and is the most superficial layer (15-30 layers thick) composed of dead/dying squamous cells

Answer 31

stratum corneum

Question 32

refers to time required for keratinocytes to form in the stratum basale and migrate to the skin surface

Answer 32

turnover, or regeneration

Question 33

Average turnover/regeneration time:

Answer 33

35 days (4-6 weeks)

Question 34

shortened turnover time will increase the thickness of the ____ _____ layer and may result in callus formation

Answer 34

stratum corneum

Question 35

As cells migrate from the basal layer to corneum they:

Answer 35

take on more keratin (keratinization)

Question 36

contains polysaccharide gel that glues the two layers together

Answer 36

basement membrane

Question 37

____ ____ is the dermoepidermal junction that resists shear forces and creates a partial barrier to some large molecules

Answer 37

Dermoepidermal Junction

Question 38

sometimes called "true skin" - much thicker than the epidermis and lies beneath it

Answer 38

Dermis

Question 39

3 functions of the dermis:

Answer 39

- gives strength to the skin - provides protection against mechanical injury and compression - Serves as a reservoir area for storage of water and electrolytes

Question 40

the _____ contains many nerves and nerve endings and is highly vascularized

Answer 40

dermis

Question 41

Composed of fine collagenous and elastic fibers - dense irregular connective tissue.

Answer 41

Papillary Layer

Question 42

____ ____ is composed of dermal papillae that project into the epidermis

Answer 42

Papillary layer

Question 43

____ ____ forms a unique pattern that gives an individual fingerprints and also makes up <20% of the dermis

Answer 43

Papillary layer

Question 44

Contains dense interlacing white collagenous fibers and elastic fibers to make the skin tough yet stretchable - dense irregular C.T.

Answer 44

Reticular layer

Question 45

The ____ layer contains many sensory receptors and nerve endings and provides attachment site for skeletal muscle of the face and scalp

Answer 45

Reticular

Question 46

AKA subcutaneous layer/superficial fascia that lies deep to the dermis and consists of mostly loose fibrous and adipose tissue

Answer 46

Hypodermis

Question 47

The 3 functions of the Hypodermis are:

Answer 47

anchors skin to underlying tissues (muscle), energy source, thermoregulation

Question 48

Lack/decreased function of tyrosinase

Answer 48

albinism

Question 49

7 functions of skin:

Answer 49

- Protection - Sensation - Flexibility - Excretion - Hormone production - Immunity - Homeostasis of body temperature