Integumentary System Notes


Published on

  • Be the first to comment

  • Be the first to like this

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Integumentary System Notes

  1. 1. The Skin (aka the Integumentary System)
  2. 2. Fun Facts About The Skin <ul><li>The skin is the largest organ in the human body. </li></ul><ul><li>It weighs about 8-10 pounds. </li></ul><ul><li>It is a tough but flexible outer covering. </li></ul>
  3. 3. Functions of the Skin <ul><li>Provides a physical barrier that protects internal organs from pathogens </li></ul><ul><li>2. Protects us from radiation, chemicals, and harmful substances in our environment </li></ul>
  4. 4. Functions of the Skin <ul><li>Keeps body fluids in to prevent drying out (desiccation) </li></ul><ul><li>Helps maintain proper body temperature </li></ul>
  5. 5. Functions of the Skin <ul><li>5. Contains nerve endings that give us information about the environment (hot, cold, touch, pressure, pain) </li></ul>
  6. 6. Layers of the Skin
  7. 7. 1. The Epidermis <ul><li>Outer layer (the layer you can see) </li></ul><ul><li>Made up of dead or dying cells </li></ul><ul><li>Upper layer is called the horny layer; made up of dead epithelial cells that constantly rub off </li></ul>
  8. 8. 1. The Epidermis <ul><li>Lower layer is made up of living cells that are constantly dividing and rising to the surface, replacing old worn-off cells </li></ul><ul><li>Hair and nails form from epidermal cells </li></ul><ul><li>Does not have its own blood supply </li></ul>
  9. 9. 2. The Dermis (true skin) <ul><li>Thicker than the epidermis and contains blood vessels </li></ul><ul><li>Contains sweat and oil glands, nerves, and the roots of hairs </li></ul><ul><li>Sweat glands keep the skin cool </li></ul>
  10. 10. 2. The Dermis (true skin) <ul><li>Nerve receptors send messages of pain, pressure, touch, hot, and cold to the brain </li></ul>
  11. 11. 3. Subcutaneous Layer <ul><li>Connects skin to muscle </li></ul><ul><li>Has fat to provide insulation, padding, and a reserve source of energy </li></ul><ul><li>Connective tissue in skin makes it elastic </li></ul>
  12. 12. Skin Color <ul><li>Melanin : pigment that gives the skin its color. More melanin is produced in response to sunlight to protect the cells from damage. </li></ul><ul><li>Blood flow : the more blood in the skin, the redder the skin </li></ul>
  13. 13. Sunburns <ul><li>The sun’s UV rays damage the outer skin’s cells; the body sends blood to the damaged cells to repair them. This results in red skin. </li></ul>
  14. 14. Skin Cancer <ul><li>Believed to be caused by ultraviolet rays of the sun. </li></ul><ul><li>Protection : </li></ul><ul><li>1. Sunscreen </li></ul><ul><li>2. Cover up </li></ul><ul><li>3. Limit exposure </li></ul><ul><li>4. Avoid tanning booths </li></ul>
  15. 15. Great Microorganisms of the World
  16. 16. 1. Fungi <ul><li>Made up of many cells with long, thin strands </li></ul><ul><li>Grow on agar </li></ul><ul><li>Usually decomposers: they live on dead tissue or animal wastes </li></ul><ul><li>Examples : molds, yeast, mushrooms </li></ul>
  17. 17. 2. Bacteria <ul><li>Single cells that may be round, rod-shaped, or spiral-shaped </li></ul><ul><li>Can be seen with a light microscope </li></ul><ul><li>Grow on agar </li></ul><ul><li>Form colonies when they reproduce </li></ul><ul><li>Decomposers </li></ul>
  18. 18. 3. Viruses <ul><li>Small; can only be seen with an electron microscope </li></ul><ul><li>Not made of cells </li></ul><ul><li>Can only grow and reproduce in a living cell </li></ul><ul><li>Cause colds, flu, measles, and mumps </li></ul>