Skin

Question 1

Functions of skin (5):

Answer 1

Protection (physical and immune), containment (prev dehydration), thermal regulation, sensation, and synthesis + storage

Question 2

–Keratinized epithelium
* Tough, protective superficial layer
* Regenerative and pigmented basal layer
* No blood vessels or lymphatics (avascular)
* Less than 1 mm, except for soles of feet

Answer 2

Epidermis

Question 3

(1-2 mm on average)
* Provide skin tone and account for strength and toughness of skin

• Most nerve terminals in here, a few penetrate
  the epidermis

Answer 3

Dermis

Question 4

Dermis: Supplied by arteries that enter its deep
surface to form a _____ of
anastomosing arteries

Answer 4

cutaneous plexus

Question 5

Which layer of epidermis is regenerative and pigmented?

Answer 5

Basal Layer

Question 6

• Most nerve endings (sensitive to touch,
  irritation/pain, temperature) found here

Answer 6

dermis

Question 7

Dermis: Dense layer of
interlacing ____ and ___ fibers

Answer 7

collagen and elastic

Question 8

____ : accidental cuts and skin tears

Answer 8

Lacerations

Question 9

Superficial Lacerations– penetrate the _____ and
sometimes ____, they bleed but
don’t interrupt the continuity of the dermis

Answer 9

epidermis. superficial layer of dermis.

Question 10

Deep Lacerations– penetrate the deep layer of ______,
extending into the subcutaneous layer or beyond,
they gape and require approximation of the cut edge
of the dermis (by suturing) to minimize scarring

Answer 10

dermis

Question 11

linear clefts in the skin that indicate the direction
of orientation of the underlying collagen fibers

Answer 11

Tension lines (cleavage lines, langer lines)

Question 12

Tension Lines: Tend to spiral ____ in the limbs and run _____in the neck and trunk

Answer 12

longitudinally; transversely

Question 13

Tension Lines: At joints, the lines are ____ to the transverse creases that
appear when the limbs are flexed

Answer 13

parallel

Question 14

Cleavage lines are also known as tension lines or

Answer 14

langer lines

Question 15

Incision or cut parallel to tension line results in

Answer 15

faster healing, less scar tissue

Question 16

slower healing and increase in scar issue occurs when an incision is cut ____ to the tension line

Answer 16

oblique or perpendicular

Question 17

a pilosebaceous unit includes:

Answer 17

hair follicles, arrector muscles of hairs, and sebaceous glands

Question 18

Where will you NOT find hair follices:

(hair follicles are generally slanted to one side)

Answer 18

palms of hands,
soles of feet, lips, and urogenital orifices

Question 19

Erects or raises hairs, causing goose bumps

• Activated under conditions of stress by
  sympathetic nervous system

Answer 19

Arrector muscles of hairs (musculi arrector pili)

Question 20

Sebaceous glands secrete what substance? What is the function of that substance?

Answer 20

sebum – an oily substance that protects
the skin from drying out

Question 21

–Lie on the side the hair is directed towards as it
emerges from the skin (side with arrector muscle)

Answer 21

Sebaceous Glands

Question 22

–Hormonal target and play a prominent role in acne
vulgaris from the formation of sebum plugs

Answer 22

Sebaceous Glands

Question 23

Contraction of the ____ causes the
hairs to stand up straighter, thereby compressing
the sebaceous glands and helping them secrete
their oily product (sebum) onto the skin surface.

Answer 23

arrector muscles (smooth muscle)

Question 24

what causes compression of the sebaceous glands, helping them secrete
their oily product (sebum) onto the skin surface.

Answer 24

Contraction of the arrector muscles causes the hair to stand up

Question 25

Evaporation of sweat from the skin provides a ____ mechanism

Answer 25

cooling

Question 26

Sweat glands are activated by ________

Answer 26

sympathetic nervous system

Question 27

_____ Sweat glands: In axilla, around nipples, in pubic area (labia majora, scrotum), in anal area. Start to function during puberty

Answer 27

Apocrine

Question 28

_____ Sweat glands: found everywhere except vermillion border of lips, external ear canal, nail beds, glans penis, clitoris, and labia minora

Answer 28

Eccrine

Question 29

____ Sweat glands: Secrete Mostly water with some ion and nitrogenous waste excretion

Answer 29

Eccrine

Question 30

_____ sweat Glands: secrete Viscous, protein and lipid-rich product that is initially odorless but can develop odor after exposure to bacteria. Also stimulated by adrenaline (NE)

Answer 30

aprocrine

Question 31

Sweat glands playing a major role in thermoregulation

Answer 31

eccrine sweat glands

Question 32

sweat glands serving as scent glands, minor role in thermoregulation

Answer 32

apocrine sweat glands

Question 33

Large, branched sweat glands that release into hair follicles

Answer 33

Apocrine sweat glands

Question 34

Sharp demarcation between the lip and the adjacent normal skin

Answer 34

Vermillion Border of Lip

Question 35

Vermillion Border of Lip: Represents change in the ____ from highly keratinized external skin to less keratinized internal skin

Answer 35

epidermis

Question 36

Epidermis is ____ on lip, so the blood vessels are closer to the surface giving the lip a reddish-pink to brown color (depending on skin tone)

Answer 36

thinner

Question 37

T/F--Vermillion Border of Lip: No sebaceous glands, sweat glands, or facial hair

Answer 37

True

Question 38

Superficial Capillary Beds--Small arteries (arterioles) within the dermis can: * ____ to fill superficial capillary beds to radiate heat (skin appears red)

Answer 38

Dilate

Question 39

Superficial Capillary Beds--Small arteries (arterioles) within the dermis can: ____ to radiate heat

Answer 39

dilate (skin appears red)

Question 40

Superficial Capillary Beds--Small arteries (arterioles) within the dermis can: **constrict** to minimize surface heat loss. How does this affect appearance?

Answer 40

skin, especially lips and fingertips, appears blue

Question 41

Modified Apocrine sweat glands that produce milk to nourish offspring

Answer 41

Mammary Glands

Question 42

Hair: In cross-section, round hairs will grow ____ and oval hairs will be

Answer 42

straighter. curly.

Question 43

Hair: Color is dependent on amount of ____ in hardened hair cells

Answer 43

melanin

Question 44

Finger and toenails * Function: protect digits and contribute to ____ sensation

Answer 44

tactile

Question 45

____ is the hard, keratinized structure made from onychocytes, organized in a lamellar pattern

Answer 45

Nail plate

Question 46

Nail plate is made from _____, organized in a lamellar pattern

Answer 46

onychocytes (These cells are a type of epithelial cell that has undergone keratinization, a process where they produce large amounts of keratin, a tough, fibrous protein that gives nails their strength and resilience) | Onychocytes are the specialized keratinocytes

Question 47

Subcutaneous Tissue (Hypodermis) also called ___

Answer 47

superficial fascia

Question 48

Located between the dermis (overlying skin) and deep fascia

Answer 48

Subcutaneous Tissue (Hypodermis)

Question 49

Subcutaneous Tissue (Hypodermis)-- composed mostly of ____ CT and stored fat

Answer 49

Loose

Question 50

T/F: Subcutaneous Tissue contains sweat glands, superficial blood vessels, lymphatic vessels, and cutaneous nerves

Answer 50

True

Question 51

____ branches from cutaneous nerves and superficial vessels reach the skin (specifically dermis)

Answer 51

Terminal

Question 52

T/F: Cutaneous nerves are both sensory and motor

Answer 52

True

Question 53

Vessels with smooth muscle in walls, arrector muscles, and sweat glands all require ___ innervation to function

Answer 53

motor

Question 54

Motor fibers are part of the ____ nervous system

Answer 54

sympathetic

Question 55

The thickness of subcutaneous tissue varies greatly, depending on ___

Answer 55

the person’s nutritional state

Question 56

Distribution of ____ tissues varies considerably in different sites in the same individual

Answer 56

subcutaneous

Question 57

T/F: Distribution of subcutaneous tissue and fat varies between the sexes

Answer 57

True (females--breasts and thighs, men--lower abdominal wall)

Question 58

Participates in thermoregulation * Insulation to retain body heat in core * Padding to protect skin from compression by bony prominences (e.g. in buttocks, bottom of foot) * Store energy in form of adipose tissue

Answer 58

subcutaneous tissue (hypodermis)

Question 59

subcutaneous tissue stores energy in the form of:

Answer 59

adipose tissue

Question 60

____ determine the mobility of the skin over deep structures

Answer 60

skin ligaments

Question 61

Skin Ligaments: Numerous small fibrous bands extend through the ___ tissue and attach the deep surface of the dermis to the underlying deep fascia

Answer 61

subcutaneous

Question 62

Longer and sparse skin ligaments = ___ skin mobility

Answer 62

more

Question 63

Another word for "Deep Fascia"

Answer 63

epimysium

Question 64

Dense, organized connective tissue layer, devoid of fat, that covers most of the body parallel to (deep to) the skin and subcutaneous tissue

Answer 64

Deep fascia

Question 65

Deep fascia is Dense, organized connective tissue layer, devoid of ___

Answer 65

fat

Question 66

Extensions from its internal surface invest deeper structures, such an individual muscles and neurovascular bundles, as investing fascia

Answer 66

Deep fascia

Question 67

Deep fascia: Thickness varies widely and, in the ____, distinct layers of deep fascia are absent

Answer 67

face

Question 68

Groups of muscles with similar functions (usually sharing nerve supply) are in fascial compartments that are separated by thick sheets of deep fascia, called ____

Answer 68

intermuscular septa

Question 69

Groups of muscles with similar functions (usually sharing nerve supply) are in _____

Answer 69

fascial compartments

Question 70

Burns: caused by thermal trauma, ultraviolet or ionizing radiation, or chemical agents. Burns are classified, in increasing order of severity, based on the ___ of skin injury and the need for surgical intervention.

Answer 70

depth

Question 71

intermuscular septa extend from surrounding fascial sleeve to attach to ____

Answer 71

bones (these compartments can contain or spread an infection of tumor)

Question 72

damage limited to epidermis

Answer 72

superficial burn

Question 73

epidermis and superficial dermis are damaged with blistering or loss of those layers * Nerve endings are damaged, making this variety the most painful * Sweat glands and hair follicles are typically not entirely damaged

Answer 73

Partial-thickness burn

Question 74

entire thickness of skin is damaged and often the subcutaneous tissue * Skin grafting is normally needed for healing * Burned area is numb since sensory endings are destroyed

Answer 74

full-thickness burn

Question 75

_______ burn – damage extends through entire thickness of skin into underlying fascia, muscles, or bone

Answer 75

Fourth-degree burn

Question 76

Burns are considered severe if they cover __or more of the total body surface area (excluding superficial burns)

Answer 76

20%

Question 77

Burns can be complicated by trauma or inhalation injury, or being caused by chemicals or ___

Answer 77

high- voltage electricity

Question 78

Burns--Risk of death increases if: * Older than 60 years old * Partial-thickness or full-thickness burns of over 40% of body surface area * Presence of ____ injury

Answer 78

inhalation injury

Question 79

A chronic, noncontagious, auto-immune skin condition that causes a rash with itchy, scaly patches, most commonly on the knees, elbows, trunk, and scalp

Answer 79

Psoriasis

Question 80

Segmented Spinal Nerves: 31 pairs of spinal nerves, each associated with a pair of ___ (8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal)

Answer 80

somites

Question 81

___ dermamyotomes give rise to all the intrinsic (deep) back muscles, as well as dermis that covers them.

Answer 81

Epaxial

Question 82

____ ramus of spinal nerve supplies motor and sensory innervation to epaxial

Answer 82

Posterior/dorsal

Question 83

____ dermamyotomes give rise to all the other skeletal muscles and dermis below the neck, including the limbs

Answer 83

Hypaxial

Question 84

= areas of skin mainly supplied by a single spinal nerve

Answer 84

Dermatomes

Question 85

Dermatomes: Each of these nerves relays ___ from a particular region of the skin to the brain

Answer 85

sensation (including pain)

Question 86

A pinched spinal nerve can cause a ___ loss of sensation (would also be accompanied by a motor deficit)

Answer 86

dermatomal

Question 87

Majority of anterior rami merge with one or more adjacent anterior rami to form the major ____

Answer 87

somatic nerve plexuses

Question 88

Therefore, most _____ nerves arising from the plexus contain fibers from multiple spinal nerves

Answer 88

peripheral

Question 89

Named nerves may be comprised of more than one spinal nerve and thus will span more than one ____

Answer 89

dermatome

Question 90

T/F: Skin on the anterior and posterior trunk have dermatome and peripheral nerve distribution that often match each other

Answer 90

True (spinal nerves do not join a plexus)

Question 91

T/F: Dermatomes and peripheral cutaneous nerve distribution match each other in the limbs and neck

Answer 91

False--do not match

Question 92

Individual peripheral nerves are often composed of multiple nerve roots levels, so the ___ of a peripheral sensory nerve crosses over different dermatomes

Answer 92

receptive field

Question 93

T/F: Although segmental nerves merge and lose their identify when plexus formation results in multisegmental peripheral nerves, the segmental (dermatomal) pattern of nerve fiber distribution remains

Answer 93

True