1. The Skin in Health & Disease
Chapter 6

2. The Integumentary System
Is formed by the skin and its APPENDAGES
Appendages include:
Hair
Nails
Glands
**Cutaneous – also refers to the skin

3. The Structure of the Skin
Two Layers
EPIDERMIS – the outermost portion
DERMIS – contains blood vessels, nerve endings & glands

4. EPIDERMIS Surface layer of skin
Contains MELANIN which is the dark pigment that colors the skin
FRECKLES are irregular patches of melanin

5. DERMIS
Extremely elastic, can stretch (as in pregnancy) with little or no damage
Well supplied with blood vessels & nerves
Thickness varies – EX: soles of feet or palm of hand (thick layers) & eyelids (thin, delicate layers)
Superficial Fascia – connects skin to surface muscles; located directly under the dermis; blood vessels that supply the skin & regulate body temperature run through the superficial fascia

6. Appendages of the Skin Sweat Glands
Coiled, tube-like structures located in the dermis & subcutaneous tissue (superficial fascia)
Regulate body temp thru evaporation of sweat
Sweat consists of H2O, small amounts of minerals & other wastes

7. Sebaceous Glands
Sac-like structures that secrete oils to lubricate skin & hair
Infected glands cause pimples!
Blocked glands cause larger growths called SEBACEOUS CYSTS

8. Hair Composed mainly of KERATIN (protein) which thicken & protect skin
Develop within a sheath called a FOLLICLE
New hair forms from cells at the bottom of the follicle

9. Protective structures made from hard keratin
Nails
Protective structures made from hard keratin
New cells form continuously at the PROXIMAL END of the nail called the NAIL ROOT

10. Functions of the Skin Protection against infection
Surface cells shed to remove pathogens
Rupture of the outermost layer of the epidermis (burns or wounds) would invite infection

11. Protection against Dehydration
The epidermis is vital in maintaining homeostasis
Regulation of Body Temperature
Protects us from the loss of excess heat & cold temperatures
Sweat glands cool the body by drawing heat out

12. Collection of sensory information
Chief sensory organ of the body
Works with the brain and spinal cord to sense pain, heat, cold, etc.

13. What can the skin tell us through observation?
COLOR
Pigment called MELANIN protects against UV radiation from the sun
An increase in melanin will darken the skin
Abnormal increases in melanin may be characteristic of certain endocrine disorders

14. PALLOR (paleness) – is caused by reduced blood flow
FLUSHING (redness) – is caused by, or often related to, a fever
JAUNDICE (yellowness) – is often associated with an increase in bile called BILIRUBIN. Causes include: HEPATITIS (liver disease) or STONES within a bile duct, blocking the flow of bile.
CAROTENEMIA – (yellow/orange discoloration) – caused by excessive intake of carrots or other deeply colored vegetables

15. LESIONS – a wound to tissue
Surface Lesions include: Rash (diaper rash, measles) &
Eruption (raised lesion, such as small pox)

16. Deep Lesions Lacerations – jagged wound caused by tearing of the skin
Ulcers – sore associated with disintegration or death of tissue

17. Fissures
Cracks in the skin as seen in athlete’s foot

18. Effects of Aging on the Skin
Wrinkles – due to a loss of fat & collagen
Dermis becomes thinner – skin loses elasticity
Pigment decreases – hair becomes grey or white
Hair does not replace itself as rapidly & becomes thinner

19. Sweat glands decrease in number causing less output of perspiration & lower ability to withstand heat
Sensitivity to cold because of poor circulation
Dryness, brittleness, flaking and/or discoloration of hair, skin & fingernails

20. Care of the Skin Proper nutrition and adequate circulation
Regular cleansing
Appropriate application of sunscreen

21. Skin Disorders
Dermatitis – is a general term for an inflammation of the skin
Causes may include:
Poison Oak/Poison Ivy
Allergies to detergents/chemicals

22. Atopic Dermatitis (Eczema)
Characterized by intense itching and skin inflammation
Can include:
Redness
Blisters
Lesions
Scaling

23. Sunburn Can cause severe burns, blisters & swelling
Excessive exposure is a risk in skin cancer

24. Melanoma The fastest growing form of cancer in the United States
Pay attention to the “ABCD” danger signs

25. ACNE A disease of the sebaceous (oil) glands
Most severe at adolescence
Some acne can be extremely severe & leave deep scarring

26. Impetigo An acute, contagious disease of STAPH or STREP origin
Can be serious enough to cause death in an infant
Blister-like lesions
Found frequently among the poor

27. Alopecia (Baldness) Most common type is “Male-Pattern Baldness”
Can happen to men & women
Causes include:
Age
Heredity
Diabetes
Thyroid disease
Malnutrition

28. Athlete’s Foot
Fungal disease caused by excessive perspiration and fungal bacteria

29. Psoriasis
Appears as a sharply outlined, red, flat area covered with silvery scales
Cause: UNKNOWN

30. Herpes
Appear as cold sores or fever blisters on the skin & mucous membranes – including the genital area

31. Shingles Caused by the chicken pox virus
Affects adults causing lesions on the skin
Pain, itching & sensitivity can last more than a year