ALL ABOUT THE

1. Created by Mark Lewis ALL ABOUT THE

2. Created by Mark Lewis Introduction to the Integumentary System • The integumentary system consists of the skin, hair nails and exocrine glands. • Has three layers: the epidermis, dermis, and subcutaneous layer

3. Created by Mark Lewis The skin • The skin is the outer covering of the body. • It protects the body from chemicals, diseases, UV rays, and physical harm. • It is the largest organ in the body. • Two layers of the skin: the epidermis and the dermis. • MODEL OF THE SKIN

4. Created by Mark Lewis

5. The outermost layer of the skin; it covers almost the entire body. About 1/10 mm thick and consists of 40 or 50 rows of simple squamous epithelial tissue. Does not contain blood (avascular) 90% of the epidermis is made of keratinocytes, which makes the skin tough, scaly, and water-resistant Melanocytes configure about 8% of the epidermis; these cells produce the brown or black pigment, melanin Langerhans cells (cells that detect light and pathogens entering the skin) and merkel cells(touch-sensing cells) round out the composition of the epidermis. Created by Mark Lewis The epidermis

6. Created by Mark Lewis Layers of the epidermis • Stratum basale- deepest layer, contains the stem cells that make all the other epidermal cells • Stratum spinosum- contains the langerhans cells and rows of prickly keratinocytes • Stratum granulosum- location where keratinocytes produce waxy lamellar granules to waterproof the skin • Stratum lucidum- made of dead keratinocytes • Stratum corneum- outermost layer, made of rows of dead keratinocytes, this layer’s purpose is protection.

7. Created by Mark Lewis

8. Created by Mark Lewis The dermis • The dermis is the deep layer of skin under the epidermis. • Made of dense connective tissue, nervous tissue, blood, and blood vessels • It is very thick, and it gives the skin its strength and elasticity.

9. Created by Mark Lewis Layers of the dermis • Papillary layer- outer layer, contains finger-like extensions called dermal papillae (increase surface area); provide nutrients and oxygen to the epidermis; its nerve cells are used to sense touch, pain, and temperature in the epidermis • Reticular layer- thick and tough deeper layer; made of dense connective tissue, containing collagen and elastic fibers; contains blood vessels to support the skin cells and nerves to sense pressure and pain

10. Created by Mark Lewis (subcutaneous layer)

11. Created by Mark Lewis Subcutaneous layer • Located under the dermis • Connects the skin, muscle, and bones • Serves as fat storage • The areolar connective tissue in this layer contains elastin and collagen fibers to allow the skin to stretch. • The fatty adipose tissue in this layer stores energy and traps heat to insulate the body.

12. Created by Mark Lewis Functions of the integumentary system

13. The skin regulates the body’s temperature. • During hypothermia, the smooth muscle in blood vessels relaxes and allows more blood into the skin(vasodilation); this pulls heat away from the core and radiates heat to the outside of the body; sweat also transports water to the surface of the skin, where it evaporates, absorbs heat, and cools the body • During hyperthermia, the skin heats the body in two ways: • The arrectorpili muscles at the base of the hair follicle form goosebumps by contracting, trapping air under hairs, and insulating the body surface. • Vasoconstriction: smooth muscles in the walls of blood vessels contract to restrict blood flow, keeping the body core warm Created by Mark Lewis Temperature homeostasis

14. Created by Mark Lewis Here’s how it works!

15. Created by Mark Lewis Vitamin D Synthesis • Vitamin D is produced when UV rays hit the skin. • The stratum basale and the stratum spinosum contain a molecule called 7-Dehydrocholesterol, which produces vitamin D3 when hit by UV rays • The kidneys later convert Vitamin D3 into Vitamin D that can be used by the body.

16. Melanin, the black or brown pigment, protects the skin from UV rays and gives the skin and hair its tan or brown color Melanin increases as UV light exposure increases. Carotene, a yellow or orange pigment, shows up in a person with low melanin. Hemoglobin, a red pigment found in red blood cells, also reveals itself in people with little melanin as a light red or pinkish color Created by Mark Lewis Skin pigmentation

17. The skin picks up touch, pain, pressure, vibration, and temperature signals. Merkel disks in the epidermis and touch corpuscles in the dermis sense the feel and shape of objects. Lamellar corpuscles in the deep dermis detect vibrations and pressure changes. Inside the dermis, there are loose nerve ends that can sense pain and temperature changes. Created by Mark Lewis Cutaneous Sensation

18. Skin, Skin Information, Facts, News, Photos -- National Geographic http://science.nationalgeographic.com/science/health-and-human-body/human-body/skin-article.html Created by Mark Lewis Now its time for a cool interactive activity on how the skin works!!!!!!!!!!!!!!!!!!!

19. Created by Mark Lewis Ancillary(accessory) Organs NAILS SWEAT GLANDS SEBACEO-US GLANDS HAIR

20. Created by Mark Lewis HAIR • Hair is made of tightly packed dead keratinocytes. • It protects the body from UV rays and insulates the body. • Hair is made of three parts: follicle, root, and shaft. • Follicle- a depression of epidermal cells into the dermis; place where keratinocytes are made • Hair root- located within the follicle and below the skin’s surface • Hair shaft- part outside of the skin and has three layers (see next slide)

21. Created by Mark Lewis Layers of the hair shaft • Cuticle- outermost layer made of keratinocytes, which are stacked like shingles • Cortex- the spindle-shaped cells in the cortex contain the pigments that give hair its color and width • Medulla- although not present in all hair, it contains pigmented cells full of keratin; when absent, the cortex continues through the middle of the hair shaft

22. Created by Mark Lewis Anatomy of the hair

23. Nails are made of sheets of hardened keratinocytes They protect the ends of the digits, and they are used for scraping and manipulating small objects. Nails grow form a deep layer of epidermal tissue known as the nail matrix, which surrounds the nail root. The new cells formed by the nail matrix force the cells of the nail root and body outward The lunula is the white part at the proximal end where some of the nail matrix is visible. The eponychium is a layer of epithelium that covers the nail body and seals the nail to prevent infection. Lets go to the next slide to see the different layers and the anatomy of a nail. Created by Mark Lewis nails

24. Created by Mark Lewis Three layers/anatomy of a nail • Nail root- portion found under the skin • Nail body- visible portion of the nail • Free edge- the end part of the nail that has grown beyond the end of the digit

25. Created by Mark Lewis Sweat(sudoriferous) Glands • Sweat glands are exocrine glands that are found in the dermis. • There are two types of sweat glands: • Eccrine sweat glands- found in most regions of the skin; produce a water and sodium chloride secretion; these glands are used to lower the body’s temperature • Apocrine sweat glands- found in the axillar and pubic regions of the body; the sweat produced by these glands exits along the hair shaft(ducts are located in the follicle)

26. Created by Mark Lewis Sebaceous glands • Exocrine glands in the dermis that produce and oily substance called sebum • Sebaceous glands are found in all parts of the skin except the palms and soles of the feet. • Sebum is brought to the surface of the skin by hair follicles • It also waterproofs and makes the skin elastic • It lubricates and shields the hair cuticles

27. Created by Mark Lewis Ceruminous glands • Special exocrine glands in the dermis of the ear canals • They produce a waxy substance called cerumen. • Cerumen protects ear canals and moistens the eardrum • It also reaps foreign substance in the ear canal • It’s made constantly and is pushed to the outside of the ear canal.

28. Cold sores- red blister filled with fluid around the mouth; caused by the herpes simplex virus Psoriasis- noncontagious skin disorder that is characterized by scaly patches of skin Vitiligo- condition in which there are white patches on the skin due to loss of the pigment, melanin Created by Mark Lewis Common skin diseases

29. Shingles- disorder that occurs when the chickenpox virus resurfaces and causes a painful rash Ingrown nail- occur when the edge of the nail grows into the skin of the toe Callus- place on the skin that has been hardened due to constant friction Created by Mark Lewis More common skin diseases

30. Did you know that an average person’s skin weighs 10 pounds and has a surface are of 20 square feet! The hair and nails are actually organs! The only places on our body without hair are the palms of the hands, plantar surface of the feet, and the lips. The digestion of the sweat produced by apocrine glands by bacteria causes body odor. The average amount of hairs on a person’s head is 120,000. We lose 30,000 to 40,000 skin cells every minute. Created by Mark Lewis Now for some fun and interesting facts !!

31. Taylor, T. (n.d.). Integumentary System. In Inner Body. Retrieved August 28, 2013, from http://www.innerbody.com/anatomy/integumentary Skin. (n.d.). In National Geographic. Retrieved August 28, 2013, from http://science.nationalgeographic.com/science/health-and-human-body/human-body/skin-article.html Brind'Amour, K. (2012, August 20). Get the Skinny on Skin Disorders. In Health Line. Retrieved August 28, 2013, from http://www.healthline.com/health/skin-disorders Created by Mark Lewis citations

32. Created by Mark Lewis THE END