Cosmetology

1. Cosmetology Integumentary System& Skin Anatomy

2. Performance Objective • Upon completion of this lesson, the student will be able to describe the integumentary system and its functions, and the anatomy of skin. The student will demonstrate these competencies by completing a written test with a minimum of 80 percent accuracy.

3. Specific Objectives • Describe the integumentary system • Name and describe the layers of skin • Name and describe the nerves of the skin • Name and describe the glands of the skin • List the functions of the integumentary system • Explain why sweating is important to survival • Explain how the skin helps to regulate body temperature • Identify the factors that affect aging of the skin • Name precautions clients can take to reduce skin aging

4. The Integumentary System • Comprised of skin, and appendages of skin: hair, nails, and sweat and oil glands • Integument means covering, and the average adult has approximately 3,000 square inches of skin • Skin weighs about 6 pounds, nearly twice the weight of the liver or brain • Skin is flexible and rugged, mostly waterproof, and can usually regenerate itself • Skin protects us from the sun and most harmful elements • Skin varies in thickness. Thinnest skin is on the eyelids; thickest skin is on the soles and palms.

5. The Layers of Skin • Epidermis • Dermis • Subcutaneous layer

6. Epidermis • The outermost and thinnest layer • Forms a protective covering for the body • Sub-layers: • Stratum corneum • Stratum lucidum • Stratum granulosum • Stratum germinativum

7. Sub-layers of Epidermis • Stratum corneum: also called the horny layer. The cells combine with a thin layer of oil to help make the stratum corneum a protective, waterproof layer. • Stratum lucidum: clear, transparent layer through which light can pass. • Stratum granulosum: Cells look like granules, and they are pushed to the surface to replace cells that are shed. • Stratum germinativum: The deepest layer of epidermis, responsible for the growth of the epidermis. Contains dark skin pigment called melanin, which protects us from the UV rays of the sun.

8. Dermis • Under the epidermis • About 25 times thicker than the epidermis • Connects the skin to tissues below it, such as fat and muscle • Two layers: • Papillary layer: Outer layer of dermis, directly underneath the epidermis • Reticular layer: Supplies the skin with oxygen and nutrients

9. Subcutaneous Layer • Fatty layer below the dermis • Varies in thickness according to the age, sex, and general health of the individual • Gives smoothness and contour to the body • Contains fats for use as energy • Acts as a protective cushion for the outer skin

10. Nerves of the Skin • Motor nerve fibers: distributed to muscles attached to the hair follicles. These muscles can cause goose bumps when someone is frightened or cold. • Sensory nerve fibers: react to heat, cold, touch, pressure, and pain. These sensory receptors send messages to the brain. • Secretory nerve fibers: distributed to the sweat and oil glands of the skin. They regulate the excretion of perspiration from the sweat glands and oil from the oil glands to the surface of the skin.

11. Glands of the Skin • Sudoriferous (sweat) glands • Sebaceous (oil) glands

12. Sudoriferous (Sweat) Glands • Excrete sweat from the skin • Almost all parts of the body have sweat glands • More numerous on the palms (we have about 3,000 sweat glands per square inch on our palms), soles, forehead, and armpits • Regulate body temperature and help to eliminate waste products from the body • Normally, one to two pints of liquids containing salts are eliminated daily through sweat pores in the skin

13. Sebaceous (Oil) Glands • Connected to the hair follicles • The glands secrete oil that lubricates the skin and preserves the softness of the hair • Found on all parts of the body except the palms and soles • Larger glands are located in the face and scalp • Normally, sebum flows through the oil ducts to the hair follicles. When the sebum hardens, the duct becomes clogged and forms a blackhead.

14. Functions of theIntegumentary System • Protection • Sensation • Heat Regulation • Excretion • Secretion • Absorption

15. Protection • Skin protects the body from injury and bacteria • The outermost layer waterproof, and is resistant to temperature, minor injuries, chemically active substances, and many forms of bacteria

16. Sensation • When sensory nerve endings are stimulated, the skin responds to heat, cold, touch, pressure, and pain • Stimulated sensory nerves send a message to the brain, which makes us react to the heat, cold, touch, pressure, or pain • “Ouch, pulling away, shivering, etc.”

17. Heat Regulation • The skin protects the body from the environment and helps maintain a 98.6 temperature • When the body is cold, the skin pores will tighten, causing goose bumps • When the body is hot, perspiration will cool the body

18. Excretion • Perspiration from the sweat glands is excreted through the skin • When perspiration occurs, salt and other chemicals are removed from the body with the sweat

19. Secretion • Sebum, or oil, is secreted by the sebaceous glands • The oil lubricates the skin, keeping it soft and pliable • Oil keeps hair soft • Emotional stress can increase the flow of sebum

20. Absorption • Absorption occurs on a limited basis • Absorption can occur with creams such as hormonal creams that are absorbed when applied to the skin

21. Why is Sweating Important? • Sweating helps to lower body temperature • People without sweat glands can easily die of heat stroke if exposed to high temperatures for even a short period of time

22. How the Skin RegulatesBody Temperature • Temperature regulation is critical to survival because changes in temperature affect the functioning of enzymes • Enzymes are critical for normal chemical reactions to occur in cells • Death can occur from high fevers because the heat destroys the enzymes by breaking up their chemical structure • When outside temperatures increase, skin produces sweat which reduces body temperature • When outside temperatures decrease, blood vessels in the dermis dilate to bring heat to the surface to warm extremities

23. Factors that AffectAging of the Skin Heredity has little to do with the overall aging of skin! Factors that affect the skin: • The sun and ultraviolet rays • The environment • Lifestyle

24. Sun and the Environment The sun and ultraviolet rays: • Approximately 80-85 percent of aging is caused by sun rays • UVA rays (also called “aging rays”) weaken collagen and elastin fibers, causing wrinkling and sagging • UVB rays (also called “burning rays”) cause tanning of the skin The environment • Pollutants in the air (auto exhaust, secondhand smoke, factory pollutants) affect the surface appearance of skin and change the underlying cells and tissues, speeding up the aging process

25. Lifestyle Smoking, drinking, taking drugs, and poor diet • Smoking causes premature wrinkling and aging of the skin • Drinking overdilates the blood vessels and can cause red splotches in the skin and eyes • Combining smoking with drinking can be devastating to the skin tissue, and can cause irreversible damage • Poor diet prevents us from having proper vitamins and nutrients necessary for maintaining healthy skin

26. Precautions to ReduceSkin Aging Protection from the sun: • Wear a moisturizer or protective lotion with a sunscreen of at least SPF 15 on all areas of potential exposure • Avoid exposure to the sun during peak hours: usually between 10:00 a.m. and 3:00 p.m. • Apply sunscreen liberally after swimming or any activity that results in heavy perspiration • Avoid exposing children younger than six months of age to the sun

27. Precautions to ReduceSkin Aging (2) Protection from the sun: • Wear a hat and protective clothing if prone to sunburn • See a dermatology for regular checkups of the skin • Perform home exams to check for new visible growths to the skin

28. Precautions to ReduceSkin Aging (3) Protection from the environment: • Follow a good daily skin care routine of washing and exfoliating (removal of dead skin cells) at night • Use daily moisturizers, protective lotions, and foundation

29. Summary • A cosmetologist who has a thorough understanding of the skin, its structure, and its functions is in a better position to give clients professional advice on scalp, facial, and hand care.