The integumentary system, consisting of the skin, hair and nails, act as a barrier to protect the body from the outside world. It also functions to retain body fluids, protect against disease, eliminate waste products, and regulate body temperature.
12. Melanin is important for protection, by absorption of Ultraviolet Radiation from the sun. All people, but especially people with Light Skin, need to minimize exposure to the sun and protect themselves from its Ultraviolet Radiation, which can Damage DNA in Skin Cells and lead to deadly forms of Skin Cancer such as MELANOMA CANCER .
13. THERE ARE NO BLOOD VESSELS IN THE EPIDERMIS, WHICH IS WHY A SMALL SCRATCH WILL NOT CAUSE BLEEDING.
4. Tiny Muscle fibers attach to Hair Follicles contract and pull hair upright when you are cold or afraid, producing what is commonly called Goose Bumps. 5. Beneath the Dermis is the HYPODERMIS , ( SUBCUTANEOUS LAYER ), A LAYER OF FAT AND LOOSE CONNECTIVE TISSUE THAT INSULATES THE BODY AND ACTS AS AN ENERGY RESERVE.
11. The production of Sebum is controlled by Hormones.
12. Oil Glands are usually connected by Tiny Ducts (Exocrine Glands) to Hair Follicles. Sebum coats the surface of the skin and the shafts of hair, preventing excess water loss and lubricating and softening the Skin and Hair.
13. Sebum is mildly toxic to some Bacteria - protection.
14. If the Ducts of Oil Glands become clogged with excessive amounts of Sebum, Dead Cells, and Bacteria, the Skin disorder ACNE can result.
15. When first wearing new shoes, the skin of the foot may be subject to friction. This will separate layers of Epidermis, or separate the Epidermis from the Dermis, and tissue fluid may collect, causing a BLISTER .
16. If the skin is subjected to pressure, the rate of mitosis will increase and create a thicker Epidermis; we call this a CALLUS .
5. THIRD DEGREE BURN - THE ENTIRE EPIDERMIS IS CHARRED OR BURNED AWAY, AND THE BURN MAY EXTEND INTO THE DERMIS. OFTEN SUCH A BURN IS NOT PAINFUL AT FIRST, IF THE RECEPTORS IN THE DERMIS HAVE BEEN DESTROYED.
6. EXTENSIVE THIRD-DEGREE BURN- POTENTIAL LIFE-THREATENING BECAUSE OF LOSS OF SKIN, WITHOUT THIS NATURAL BARRIER, LIVING TISSUE IS EXPOSED TO THE ENVIRONMENT AND IS SUSCEPTIBLE TO INFECTION AND DEHYDRATION.