| STRUCTURE AND FUNCTIONS OF SKIN | | | | D is a vital for normal growth and functioning of |
| The skin is the largest organ in the body, making | | | | the body. |
| up about one-sixths of total body weight. The | | | | Interacting With The Environment |
| functions of our skin go well beyond being a mere | | | | Our skin contains millions of nerve receptors |
| cosmetic covering of our bodies. It can be | | | | which sense touch, pain and temperature. It is |
| credited for the following functions as well: | | | | these nerves that enable us to feel and respond |
| Temperature Regulation | | | | to our environment. For instance, pain receptors |
| Our skin reacts to the external temperature by | | | | when stimulated by a painful stimuli (such as a |
| either raising goose bumps, or causing us to | | | | sharp object), causes a reflex withdrawal of the |
| sweat. It does this to try to maintain our body | | | | limb, thus serving to protect it from further injury. |
| temperature at just the right level (unlike our cold | | | | Fat Stores |
| blooded cousins), and it does so without our | | | | There is a layer of fat under the skin, which |
| voluntary input. | | | | whilst unsightly, serve several important functions. |
| Protection | | | | This layer of fat serves to insulate our bodies |
| As the external covering of our bodies, it | | | | from heat loss. It also serves as a store of |
| protects us in more ways than we can imagine. It | | | | reserve calories, which can be drawn on during |
| makes us pretty much water proof, so that we | | | | times of starvation. |
| don't swell up every time we come into contact | | | | Physical Appearance |
| with water. It prevents water from our bodies | | | | The condition and appearance of our skin, is often |
| from evaporating uncontrollably, preventing us | | | | a reflection of our general health and well-being. |
| from drying up on a hot day. There is the physical | | | | There are thriving industries which support the |
| protection from injury, as well as protection from | | | | millions who seek to have better looking skin. The |
| ultraviolet radiation and bacteria. | | | | decoration of skin with tattoos, paints and |
| Making Vitamin D | | | | jewelery can be important in different societies |
| Our skin makes Vitamin D when it comes into | | | | and cultures. |
| contact with ultraviolet rays from the sun. Vitamin | | | | |