Skin and Burns

Question 1

List the 4 primary types of tissue

Answer 1

1. nervous tissue
2. muscle tissue
3. epithelial tissue
4. connective tissue

Question 2

nervous tissue

Answer 2

Internal Communication

• brain
• spinal cord
• nerves

Question 3

Muscle Tissue

Answer 3

Contracts to cause movement

• muscle attached to bone
• muscle of heart
• muscle of walls of hollow organs

Question 4

Epithelial Tissue

Answer 4

Forms boundaries between different environments. Protects, secretes, absorbs, and filters.

• skin surface (epidermis)
• lining of GI tract organs and other hollow organs

Question 5

Connective Tissue

Answer 5

Supports, protects, binds other tissue together

• bones
• tendons
• fat and other soft padding tissue

Question 6

What are the 3 Structural Layers of the Skin

Answer 6

1. epidermis
2. dermis
3. hypodermis

Question 7

characteristics of the epidermis

Answer 7

• avascular
• dynamic steady state due to keratinocytes constantly dying
• replaced every 25-45 days

Question 8

list the 5 epidermal layers

Answer 8

1. stratum corneum
2. stratum lucidum
3. stratum granulosum
4. stratum spinous
5. stratum basale

Question 9

list the characteristics of the epidermal layer - stratum basale

Answer 9

• single layer of dividing stem cells
• new cells push older ones to the surface
• contains melanocytes (pigments)

Question 10

function of the stem cells

Answer 10

divide to produce keratinocytes

Question 11

function of keratinocytes

Answer 11

produce keratin

Question 12

function melanocytes

Answer 12

produce melanin

Question 13

function of Merkel cells

Answer 13

touch receptors

Question 14

function of langerhans cells

Answer 14

(macrophages) activate immune response

Question 15

list the characteristics of the dermis

Answer 15

• bulk of the skin
• flexible and strong
• made from connective tissue
• contains sweat glands

Question 16

Bloody Supply of the skin

Answer 16

Hypodermis: dense capillary network which projects through dermis and is controlled by pre capillary sphincters

Question 17

list the 6 major functions of the skin

Answer 17

1. protection
   - physical
   - chemical
   - biological
2. sensation
3. metabolic function
4. blood reservoir
5. excretion
6. temperature regulation

Question 18

Function of the Skin - physical protection

Answer 18

• keratin and oily secretions blocks most water

Question 19

Function of the Skin - chemical protection

Answer 19

• low pH prevents bacteria
• defensins secreted to kill bacteria
• melanin protects DNA in underlying cells from UV damage

Question 20

Function of the Skin - biological barrier

Answer 20

macrophages dispose of viruses and bacteria that penetrates epidermis

Question 21

what are the 3 types of receptors for sensation

Answer 21

• Nocioceptors (pain)
• thermoreceptors
• mechanoreceptors (touch)

Question 22

Function of the Skin - Metabolic

Answer 22

Synthesis of Vitamin D

Question 23

Functions of the Skin - blood reservoir

Answer 23

hold up to 5%

Question 24

Functions of the skin - excretion

Answer 24

waste and salt is excreted via sweat

Question 25

what are the 2 mechanisms of skin repair

Answer 25

1. regeneration 2. fibrosis (usually involves both)

Question 26

characteristics of skin repair - regeneration

Answer 26

- replaces destroyed tissue with the same kind of tissue | - restored to normal os damage is minor (only epidermis) and the stem cells of epidermis are still in tact

Question 27

characteristics of skin repair - fibrosis

Answer 27

- replaces destroyed tissue with scar tissue | - damage that includes dermis = fibroblasts

Question 28

list the 3 stages of skin repair

Answer 28

1. inflammation and formation of blood clot 2. formation of granulation tissue 3. regeneration and fibrosis

Question 29

lis the 4 different types of burns

Answer 29

- thermal - electrical - chemical - radiation

Question 30

what are the 4 levels of burn classification

Answer 30

1. Superficial burn 2. Superficial partial thickness burn and deep partial thickness burn 3. full thickness burn 4. subnormal burn

Question 31

list the characteristics of a superficial burn

Answer 31

- only the epidermis - no barrier function impairment - heals in a week by itself without scarring - sunburn

Question 32

list the characteristics of a partial thickness burn

Answer 32

- destruction of entire epidermis +/- no more than 1/3 of dermis - vessels injured - blisters = epidermis lifts off - nerve endings exposed - blood flow adequate and low infection risk - heals in 3 weeks - low scarring risk

Question 33

list the characteristics of deep partial thickness burns

Answer 33

- destruction of epidermis and majority of dermis - no blisters - wound is white and dry - compromised blood flow - infection risk - low pain due to destruction of nerve endings - 3+ healing

Question 34

list the characteristics of full thickness burns

Answer 34

- complete destruction of epidermis and dermis - no cells - dead avascular burn = white and waxy or charred - does not heal spontaneously - requires a skin graft

Question 35

list the characteristics of subnormal burns

Answer 35

- complete destruction of epidermis and dermis and underlying tissue - wound is charred, dry, brown or white without sensation - treatment = amputation - complete destruction = no skin graft

Question 36

contracture treatment modalities

Answer 36

- stretching - splinting - massage - grafting - silicone gels