1. Skin

3. The skin is the largest organ in the human body

4. Functions Protection- Temperature- keeps important things in (water)
keeps bad things out (bacteria)
Temperature-
blood vessels run through the skin and help regulate temperature.
When the body is too warm, the blood vessels expand to increase blood flow, getting heat out of the body faster.

5. Functions Eliminating waste- Gathering information- Vitamin D-
Perspiration (sweat) removes bacteria from the body.
Gathering information-
Nerves provide information for the rest of the body.
Examples of information: pain, pressure, temperature
Vitamin D-
Skin cells produce Vit. D in the presence of sunlight.
Vit. D is important for healthy bones because it helps the bones absorb calcium.

6. Epidermis
Outer layer
No nerves or blood vessels.

7. Epidermis Life of the epidermis:
Cells form low in the epidermis and mature as they move up (2 weeks)
The cells die and become a part of the surface (2 weeks)
Dead cells are shed and replaced.

8. Epidermis Shedding carries away bacteria.
Dead cells provide more protection than live cells.

9. Epidermis Melanin- Produced deep in the epidermis.
Pigment that gives your skin its color.
Helps prevent your skin from burning

10. Dermis Inner layer of skin. Between the Epidermis and the fat layer.
Contains nerves, blood vessels, sweat glands, hair follicles, and oil glands.

11. Dermis Sweat reaches surface through pores. Hair is dead cells.
It helps waterproof hair
and keeps skin moist.
Hair growth starts
in the hair follicles in the
dermis.

12. Keeping Skin Healthy Diet-
Helps with growth and replacement of hair, nails, and skin cells.
Drinking water helps to replace water that is lost through sweat.

13. Keeping Skin Healthy Clean Skin- Limited sun exposure-
Gets rid of dirt and bacteria.
Helps control oil.
Limited sun exposure-
Helps prevent cancer
Prevents wrinkled, leathery skin