“GETTING UNDER YOUR SKIN”

1. “GETTING UNDER YOUR SKIN”

2. What do you think this means...? Right now you are wearing an air-conditioner, a blanket, a thermometer, a garbage disposal, a waterproof suit, a chemical factory and an oil refinery.”

3. Two Layers of Skin • Epidermis (outermost covering)  Made of epithelial cells  Is avascular (no blood vessels) • Dermis (true skin)  Made of connective tissue  Is vascular (has blood vessels)

4. Layers of the Epidermis • Squamous Germination  Innermost epidermal layer Active layer of cell division (mitosis) Continually reproduces and new cells move toward the surface (allows skin to self-repair) • Stratum Corneum (outermost layer) Horny layer of skin (cells are dead) Keratin replaces cytoplasm in the cells as they approach the surface (waterproofs the skin) Slightly acidic – destroys many organisms –first line of defense against surface bacteria

5. Layers of the Epidermis (continued) 3. Pigment Layer  Layer that contains melanocytes which produce the brown pigment melanin that give the skin its color  Ultra-violet rays produce an increase in melanin = tan or sunburn  Albinism – absence of melanin Freckles – patches of melanin

6. We get a new outer skin layer every 27 days!Flat and scale-like cells of the stratum corneum flake off

7. Dermis Layer (Corium or True Skin) • Thicker, inner layer of skin • Framework of elastic connective tissue (enables skin to stretch) • Number of elastic fibers and collagen decrease with age = wrinkles, sags, and lines • Contains blood vessels, nerves, involuntary muscle, sweat and oil glands, and hair follicles • Sensory nerves end in nerve receptors which are sensitive to heat, cold, touch, pain, and pressure

8. Dermal Papillae • Ridges and grooves in upper layer of dermis that push into the stratum germinativum (Unique to each person) • Create permanent ridges in fingers, palms, and soles of feet • Provides maximum resistance to slipping when grasping and holding objects • Ridges create fingerprints used in identification

9. Subcutaneous Tissue or Hypodermal Layer  Lies under the dermis and carries major blood vessels and nerves to the skin above it • Made up of loose connective tissue (adipose) and contains about ½ of the body’s stored fat • Connects skin to underlying muscles Adipose Tissue

10. 3 Function of Subcutaneous Tissue • Cushions the body • Insulates the body • Site of subcutaneous injections (large blood vessels)

11. Sudoriferous (Sweat Glands) • Approximately 3 million sweat glands throughout the body • Most are found under the arms (axilla), palms of hands, soles of the feet, and forehead • They are tubular with a coiled base in the dermis and a tube-like duct which extends to form a pore in the epidermis • Water filters through the thin walls from surrounding tissue • Water is mixed with small amounts of waste material such as ammonia and uric acid

12. Sudoriferous (Sweat Glands) • These glands can be activated by heat, pain, fever, and nervousness • On an average summer day, these glands will pump out about 2 quarts of fluid

13. Sudoriferous Glands – Two Types • Eccrine – Produces perspiration and functions throughout life  Assists in body heat regulation  Perspiration is 99% water and average fluid loss is 500 ml.per day 2. Apocrine – (larger than eccrine glands)  Found in axilla and genitalia  Enlarges and begins to function during puberty  Secretes a thick milky secretion  Skin bacteria breaks these secretions and causes the odor you smell

14. Sebaceous Glands (Oil Glands) • Secretes oil or sebum for hair and skin which protects your hair and skin from drying out • Makes skin waterproof • These glands increase five-fold between ages 10-19 • Usually opens onto a hair follicle

15. Plugged Sebaceous Glands • Plugged sebaceous glands (oil glands) will produce blackheads or pimples • Acne Vulgaris is an inflammation of sebaceous glands

17. Hair • Millions cover the body • Anatomy of a hair: • Root – part of the hair implanted in the skin • Shaft – part of the hair which projects from the skin • Hair Follicle – epidermal tube-like structure that holds the hair root (extension of the epidermis deep into the dermis) • Papilla – tuff of tissue at the bottom of the follicle that contains blood vessels • Hair Bulb – Where hair growth starts

18. Hair Follicle Outer layer = cortex Inner layer = medulla

19. How Hair Grows (Cycles) • Hair is produced in the hair bulb • Blood vessels in the papilla supply the hair bulb with nourishment • Division of cells in the hair follicle gives rise to new hair • These cells divide and undergo keratinization • Hair grows longer as cells are added to the base of the hair root

20. Critical Thinking Based on your knowledge of hair growth cycles, why does your hair grow back when you use products such as Nair to get rid of hairs on your body?

21. How Hair Grows As long as cells in the papilla of the hair follicle remain alive, new hair will replace any that is cut or plucked.

22. How Hair Grows Alopecia Hair loss of any kind.

23. Arrector Pili Muscle • Involuntary muscle that attaches to the lower end of the hair follicle near the bulb and the other end is attached to connective tissue in the dermis • Produces “goose pimples” or “goose bumps” to trap heat and keep the body warm

24. Nails • Nail is formed in the nail bed or matrix • Epidermal cells fused together and fill with keratin

25. 7 Functions of the Integumentary System • Protective covering • Regulates body temperature • Manufactures Vitamin D • Sensory Function • Temporary storage of fat, glucose, water, and salts • Screens out harmful ultraviolet readiation • Absorbs certain drugs

26. Skin and Microorganisms • Intact skin = best protection against pathogens, toxins and water loss • Skin generally too dry for microbial growth – they do grow in moist areas • Most skin bacteria associated with hair follicles or sweat glands • Underarm perspiration odor caused by bacteria and perspiration

27. The best way to prevent the spread if disease is by hand washing

28. Burns • First Degree Burns • Involves only the epidermis • Sunburn is an example • Symptoms: redness, pain, and small amount of swelling • Treatment – apply cool water and analgesics for pain • Healing Time: 3 – 6 days and tissue destructions is minimal

29. Burns • Second Degree Burn • May involve the epidermis and the dermis • Symptoms: Pain, swelling, redness and blisters (Skin may be exposed to infection) • Treatment: Pain medication and dry sterile dressing over open skin areas (DO NOT POP THE BLISTERS!) • Healing Time – 2-3 weeks with minimal cosmetic defects ( May have change in skin color or pigmentation)

30. Burns • Third Degree Burns • Destruction of the epidermis, dermis and sometimes the subcutaneous layer • Can involve underlying muscles and even bones • Symptoms: loss of skin, eschar, and there may be no pain due to damaged nerves • May be life- threatening damage depending on the amount of skin and fluid loss, as well as plasma • Treatment: • Immediate hospitalization • Prevent infection and skin contractures • Fluid replacement • Skin grafts as soon as possible

31. Burns

32. Rule of Nines • Treatment and possibility of recovery from burns depend on the total body area affected and the severity of the burn • It is used to measure the percent of the body burned.

33. Rule of Nines • The body is divided into 11 areas and each area accounts for 9% of the total body surface • Major Burns: • Second degree over 25% of adult body surface area (b.s.a.) or more than 20% of a child’s body surface area • Third degree burn over more than 10% of adult body surface area.

34. Practical Application • Patrick was involved in a fire when his race car crashed. He burned his face, entire right arm, back, buttock, and front of right leg. What percent of his body was burned? • 40.5%

35. Now, do you know what this means…? Right now you are wearing an air-conditioner, a blanket, a thermometer, a garbage disposal, a waterproof suit, a chemical factory and an oil refinery.”