integumentary system. skin largest organ of the body forms a barrier that protects us from the...

Integumentary Integumentary SystemSystem

SKINSKIN• Largest organ of the body • Forms a barrier that protects us from

the outside world, especially from infection and injury

• Prevents the loss of water and other body fluids

FunctionsFunctions• Protects us from the

toxic effect of ultraviolet irradiation by producing melanin

• When exposed to sun's rays, skin produces vitamin D3, an essential step in the formation of vitamin D which helps in bone formation.

• Helps to recognize heat, cold, touch, and pain by nerve endings and sensory receptors.

• Regulates body temperature –when we are hot, we sweat. When we are cold we shiver.

Functions cont.Functions cont.

• Stores fat, sugar, water, vitamins, and salts.

• Absorbs some substances, such as medications like those for motion sickness.

• Excretes salt, water, and waste through perspiration.

Structure of the SkinStructure of the Skin• 3 main layers

– Epidermis– Dermis– Subcutaneous

• Epidermis– Top layer– Made up of 4 other

layers

• Dermis– connective tissue– blood vessels – nerve endings– hair follicles– sweat glands – sebaceous glands

• Subcutaneous– contains fatty tissue– attaches dermis to the

underlying tissues (e.g. the muscles).

Skin ColorSkin Color

Color determined bypigments in theepidermis of the skin.

Abnormal skin colors can indicate disease.

Erythema• reddish color• can be caused by either

burns or a congestion of blood in the vessels.

Jaundice• yellow discoloration of the

skin• May indicate bile in the

blood as a result of liver or gallbladder disease.

Cyanosis• bluish discoloration of the

skin • insufficient oxygen.

Albino• The absence of color

pigments

Jaundice Erythema

• Cyanosis • Albino

Skin EruptionsSkin Eruptions• Seven types of skin eruptions

– 1. macules– 2. papules– 3. vesicles– 4. pustules– 5. crusts– 6. wheals– 7. ulcers

Skin EruptionsSkin Eruptions• Macules – flat spots on the skin, such as freckles.

Skin EruptionsSkin Eruptions• Papules – firm, raised

areas. Moles are a good example

Skin EruptionsSkin Eruptions• Vesicles – blisters,

or fluid-filled sacs, such as those seen in chickenpox.

Skin EruptionsSkin Eruptions• Pustules – pus-

filled sacs such as those seen in acne or pimples.

Skin EruptionsSkin EruptionsCrusts – areas of dried pus and blood,

commonly called “scabs”.

Skin EruptionsSkin Eruptions• Wheals – itchy,

elevated areas with irregular shape; hives and insect bites for example.

UlcersUlcers

• Deep loss of skin surface• May extend down into dermal layer• Occasional bleeding• Scars will form

Stage 1 UlcerStage 1 Ulcer• Damage is limited to the top two

layers of skin. The skin is not broken and the redness does not turn white when touched.

Stage 2 UlcerStage 2 Ulcer• Damage extends beyond the top two

layers. The skin is slightly broken. The sore appears to be an abrasion, blister or small crater.

Stage 3Stage 3• Damage down to the superficial

layers of the skin, adipose tissue, and the muscle. The ulcer appears as a deep crater.

Stage 4Stage 4• Damage includes destruction of all

soft tissue structures and involves bone or joint structures.

• What is Acne?– A skin condition in adolescence,

affecting the face, chest, and back. 

• What causes Acne?• Overreacting and inflammation of the

sebaceous glands cause acne• Oily sebum accumulates in the hair follicles,

producing pustules and black heads. • Severe cases can be treated with antibiotics.

• How to cure Acne• Ingredients • · 3 teaspoons of salt

· warm water• Add the salt to the water in your bathroom basin and wash

your face thoroughly twice a day for best results.It will leave your skin free of oil.

• First, gently wash your face with a mild soap and rinse well. Next, apply the vinegar to the face at night before going to bed. Apply with cotton ball and let sit for 5-10 minutes then rinse off with cool water. A ton of individuals have reported amazing results from this treatment.

DermatitisDermatitis

• Not a single disease -- rather the name that covers those skin conditions in which inflammation is the key feature.

• The chief signs of dermatitis are: redness, a rash, and pain or itching.

Dermatitis

VerrucaeVerrucae• Commonly called warts• Caused by viral infection of the skin• A rough, hard, elevated, rounded surface

forms on the skin• Some warts remove spontaneously, but

others must be removed with electricity, liquid nitrogen, acid, or chemicals.

Verrucae

PsoriasisPsoriasis• Chronic, noncontagious, inherited skin

disease.• Symptoms include thick, red areas

covered with white or silver scales.• There is no cure; however, treatment

includes coal/tar or cortisone ointments; ultraviolet light; and/ or scale removal

Psoriasis

Skin CancerSkin Cancer• Takes on different forms such as basal cell

carcinoma, squamous cell carcinoma, and malignant melanoma.

• Frequently develops from a mole or nevus that changes in color, shape, size, and texture.

• Bleeding and itching of a mole can also indicate cancer.

• Exposure to the sun, irritating chemicals, or radiation are the usual causes of skin cancer.

• Treatment involves surgical removal of the cancer.

Abnormal Moles (ABCD)Abnormal Moles (ABCD) ~ A - Asymmetry

Draw a line through the middle of the mole. If the halves don't match, the mole is asymmetric and more likely to be abnormal.

~ B - Border The borders of a typical moles are not well defined or can look scalloped with notches between the scallops.

~ C - Color An uneven color throughout the mole is more likely a sign of abnormality.

~ D - Diameter Most melanomas spread horizontally. Look for moles that are enlarging in diameter greater than 1/4 inch (about the size of a pencil eraser).

Melanoma

Skin FactsSkin Facts• The skin is constantly renewing itself by growing

new cells at the lowest layer and shedding the old skin cells from the surface. The average person might shed 40 pounds of skin cells in her lifetime!

• Feel like you are slowing down as you age? You are right, at least in regards to your skin. It takes about 14 days for a 20 year old to replace his epidermis. For a 50 year old, the time more than doubles, taking 37 days.

• It weighs approximately 9 pounds.

•Q & A – ~Why do fingers and toes wrinkle in the

bathtub?

The outermost layer of the skin swells when it absorbs water. It is tightly attached to the skin underneath, so it

compensates for the increased area by wrinkling.