Chapter 5

Question 1

The first and foremost barrier
Functions: Protection, body temp regulation, cutaneous sensations, metabolic functions, blood reservoir, excretion of wastes

Answer 1

Skin

Question 2

Epidermis
Dermis

Answer 2

2 layers of skin…

Question 3

Superficial region
Consists of epithelial tissue (keratinized stratified squamous)
Avascular (no blood vessels)
Outer protective shield of body

Answer 3

Epidermis

Question 4

Underlies epidermis
Mostly fibrous connective tissue
Bulk of skin
Contains nerves, blood vessels, and lymphatic vessels
Contains epidermal hair follicles, oil glands, and sweat glands

Answer 4

Dermis

Question 5

Subcutaneous layer deep to skin
Not a part of the skin, but shares some functions
Mostly adipose tissue that absorbs shock and insulates
Anchors skin to underlying structures (mostly muscle)

Answer 5

Hypodermis

Question 6

Keratinocytes
Melanocytes
Dendritic cells
Tactile (Merkel) cells

Answer 6

Four cell types found in epidermis…

Question 7

Produce fibrous keratin

Answer 7

Keratinocytes

Question 8

Spider-shaped cells, produce melanin

Answer 8

Melanocytes

Question 9

Star shaped macrophages that patrol deep epidermis

Answer 9

Dendritic cells

Question 10

Stratum corneum
Stratum lucidum
Stratum granulosum
Stratum spinosum
Stratum basale

Answer 10

Five skin layers

Question 11

Deepest epidermal layer, one row of actively mitotic stem cells

Answer 11

Stratum basale

Question 12

Several layers of keratinocytes unified by desmosomes

Answer 12

Stratum spinosum

Question 13

Third portion in thin skin
Typically one to five layers of flattened cells, organelles deteriorating; cytoplasm full of lamella granules and keratohyalin

Answer 13

Stratum granulosum

Question 14

Most superficial layer of epidermis, 20-30 layers of dead cells, essentially flat membranous sacs with keratin

Answer 14

Stratum corneum

Question 15

Found only in thick skin; thin translucent band of dead keratinocytes; lies superficial to the stratum granulosum

Answer 15

Stratum lucidum

Question 16

First layer in dermis
Thin, superficial layer made of areolar tissue
Interlacing collagen fibers form a loosely woven mat of small blood vessels
Includes dermal papillae

Answer 16

Papillary layer

Question 17

Fingerlike projections that project into the epidermis

Answer 17

Dermal papillae

Question 18

Mounds that dermal papillae rest on top of
Cause overlying epidermis to form epidermal ridges

Answer 18

Dermal ridges

Question 19

Dermal ridges + Epidermal ridges
Enhance gripping ability
Create fingerprints

Answer 19

Friction ridges

Question 20

Second layer in dermis
Most of dermal thickness and made up of dense irregular connective tissue
Collagen fibers provide strength and resiliency
Large networks of blood vessels

Answer 20

Reticular layer

Question 21

Network of blood vessels between reticular layer and hypodermis

Answer 21

Dermal vascular plexus

Question 22

Collagen fibers running parallel to skin surface
Externally invisible
Helps surgeons make incisions that will heal quickly

Answer 22

Tension lines

Question 23

Dermal folds near joints
Where the dermis closely attached to the underlying structures

Answer 23

Flexure lines

Question 24

Extreme stretching of skin causing dermal tears, leaving silver/white scars
“stretch marks”

Answer 24

Striae

Question 25

Acute, short term traumas to skin creating fluid filled pockets that separate epidermal and dermal layers

Answer 25

Blisters

Question 26

Melanin Carotene Hemoglobin

Answer 26

Three skin pigments:

Question 27

Only pigment made in skin, made by melanocytes Packages into melanosomes that are sent to shield DNA of keratinocytes from damaging UV sunlight Freckles, and pigmented moles are local accumulations of melanin

Answer 27

Melanin

Question 28

Clumping of elastic fibers, causing skin to become leathery UV light destroys folic acid

Answer 28

Excessive sun exposure

Question 29

Yellow to orange pigment Most obvious in palms and soles Accumulates in stratum corneum and hypodermis Can be converted to vitamin A for vision and epidermal health

Answer 29

Carotene

Question 30

Pinkish hue of fair skin is due to lower levels of melanin

Answer 30

Hemoglobin

Question 31

Blueness in skin, low oxygenation of hemoglobin; sign of respiratory issues

Answer 31

Cyanosis

Question 32

Emotional stress, low blood pressure, anemia

Answer 32

Pallor/Blanching

Question 33

Yellowness, liver disorders

Answer 33

Jaundice

Question 34

Redness, embarrassment

Answer 34

Erythema

Question 35

Bruising; result of blood leakage from damaged blood vessel beneath skin

Answer 35

Red/Purple/Yellow marks

Question 36

Hyperpigmentation, thickened skin in folds Endocrine disorders

Answer 36

Brown or black patches

Question 37

Consists of dead keratinized cells (hard) Produces hair follicles Warns of insects on skin Guards against physical trauma Protect from heat loss Shield skin from sunlight

Answer 37

Hair

Question 38

Sac that hair grows in, considered skin organ

Answer 38

Hair follicle

Question 39

Where keratinization is still going on

Answer 39

Root

Question 40

Where keratinization is complete Projects from skin, extends halfway down portion of hair embedded in skin

Answer 40

Shaft

Question 41

Protective covering for fingers and toes Scale-like modifications of epidermis that contain hard keratin 3 parts - free edge, nail body, root

Answer 41

Nail

Question 42

Epidermis underneath keratinized nail plate Bed is the deepest layers of epidermis

Answer 42

Nail bed

Question 43

Abundant on palms, soles, and forehead Ducts connect to pores Function in thermoregulation Secrete sweat

Answer 43

Eccrine sweat glands

Question 44

Ducts emptying into hair follicles Function unknown but may act as sexual scent gland Secrete viscous milky or yellowish sweat Contains fatty substances and proteins Bacteria break down sweat leading to BO

Answer 44

Apocrine sweat glands

Question 45

Oil glands; Most develop from hair follicles and secrete into hair follicles Secrete sebum

Answer 45

Sebaceous glands

Question 46

Protection Body temp regulation Cutaneous sensations Metabolic functions Blood reservoir Excretion of wastes

Answer 46

Skin functions:

Question 47

Swelling caused by an abnormal growth of tissue 1. Benign - non cancerous, doesn't spread 2. Malignant - cancerous, can spread

Answer 47

Tumor

Question 48

Most common skin cancer, least likely to spread Begins as a papule, enlarges and develops central crater Cured by surgical excision

Answer 48

Basal cell carcinoma

Question 49

Second most common type of skin cancer Can spread to other organs Usually reddened papule on scalp, ears, lower lip, or hands Good prognosis if treated by radiation therapy or removed surgically

Answer 49

Squamous cell carcinoma

Question 50

Cancer of melanocytes, most dangerous types Can arise from a pre-existing mole or normal skin

Answer 50

Melanoma

Question 51

Tissue damage caused by heat, electricity, radiation, or certain chemicals Immediate threat is dehydration and electrolyte imbalance

Answer 51

Burns

Question 52

Epidermal damage only; localized redness, swelling, pain

Answer 52

First-degree burn

Question 53

Epidermal and upper dermal damage; blisters appear

Answer 53

Second-degree burn

Question 54

Entire thickness of skin involved; Skin color turns gray-white, cherry red, or blackened No swelling seen b/c nerves are destroyed

Answer 54

Third-degree burn

Question 55

Involves deeper tissue, such as muscle or bone

Answer 55

4th-degree burn