integumentary system

skin

• body’s outer covering

• largest organ

• composed of 3 layers

accessory organs

• hair follicles

• finger and toe nails

• skin glands

functions of the integumentary system

• protection

  • first line of defense against bacteria and viruses

  • protects underlying structures from UV radiation and dehydration

• body temperature regulation

  • if too hot: dermal blood vessels dilate and more blood is sent to the surface so heat escapes

  • if too cold: dermal blood vessels constrict and prevent heat from escaping

• vitamin D production

  • skin must have sunlight

  • needed for calcium absorption

• sensation

  • has nerve receptors that detect heat, cold, and pain

• excretion

  • perspiration aids in cooling

  • results in loss of water and minerals

skin structure

epidermis

• outermost layer of skin

  • epithelial tissue

  • no blood vessels

  • no bleeding if scraped

• contains keratin

  • hard protein that makes up hair and nails

• melanocyte (skin cell) makes the pigment melanin

  • gives skin its color

• skin color changes

rubor or erythema

• red

• flushing of the skin when blushing due to dilated blood vessels

pallor or pale

anxiety and cold can cause blood vessels to constrict

cyanosis

bluish tint to the skin when it is not getting enough blood

dermis

• thick layer beneath the epidermis

• contains blood vessels, arteries, veins, capillaries, and nerves

• contains sweat glands and hair follicles

  • dermal puncture and finger stick both draw blood from capillaries in the dermis

subcutaneous layer

• connective tissue

• composed of adipose tissue (fatty layer) and larger blood vessels

• subcutaneous injection site

• third layer of skin

sudoriferous glands

sweat glands

eccrine glands

• distributed throughout the body

• produce fluid to regulate body temperature

apocrine glands

• present in the axilla and pubic area

• responsible for odor as bacteria break down organic substances

sebaceous glands

• secretes an oily substance called sebum

• adds a protective layer and prevents fluid loss

neoplasm

• means “new growth”

• does not indicate if it is malignant (cancerous) or benign

alopecia

hair loss

acne vulgaris

• black heads

• white heads

• pustules

cellulitis

bacterial infection

dermatitis

inflammation with rash

eczema

itchy, red, scaly rash

herpes simplex (cold sore)

• blisters

• mouth, lips, face

impetigo

• bacterial infection

• itchy, oozing skin

keloid

an overgrowth of scar tissue

nodule

small growth under the skin

petechiae

ruptured skin capillaries

pediculosis

lice infestation

ringwom (tinea corporis)

• fungus infection

• circular lesions

rosacea

• dilation of blood vessels

• redness

basal cell carcinoma

• most common

• sun exposure

• new growth does not heal

squamous cell carcinoma

• sun exposure

• spreads to surrounding tissues (metastasize)

• common on face and head

• less common than basal cell

malignant melanoma

• most aggressive

• sun exposure

• itchy

• bleeding mole with changes

how is the severity of burns based on?

• extent of body surface area

  • rule of nines is used to estimate % of the body surface area affected by a burn

• degree of burn

  • first degree

  • second degree

  • third degree

rule of nines

1st degree burn

• superficial (epidermis)

• pain, redness, swelling (sunburn)

2nd degree burn

• partial-thickness

• includes subcutaneous tissue

• pain, redness, swelling, blisters

3rd degree burn

• full-thickness

• all layers of skin, muscle possible bone

• skin appears charred

• always requires medical attention

integumentary system

the body’s outer covering composed of skin, hair follicles, nails, glands, and blood vessels

what is not a function of the integumentary system?

• protection from UV radiation

• digestion

• protection from bacteria

• body temperature regulation

digestion

what is not an accessory organ of the integumentary system?

• hair follicles

• finger and toe nails

• dermis

• skin glands

dermis

which layer of the skin contains blood vessels and sweat glands?

• dermis

• epidermis

• subcutaneous layer

dermis

which form of skin cancer is the most aggressive?

• basal cell carcinoma

• melanoma

• squamous cell carcinoma

melanoma

which disorder of the skin is an overgrowth of scar tissue?

• keloid

• eczema

• impetigo

• cellulitis

keloid

what is used to estimate % of the body surface area affected by a burn?

• body surface rule

• BMI rule

• rule of degrees

• rule of nines

rule of nines