Integumentary System

The integumentary system makes up the skin, hair and nail system. The integumentary system includes: *Skin: The skin is the body's largest organ. However, it's width is only a few millimeters thick. It acts as a barrier against wetness, sun damage, and infection. The skin also penetrates moistures from moving into further layers of the skin. There are two layers of the skin: -Epidermis: This is the top layer of the skin and it is the visible part of the skin that does the work of protecting the body against wetness, sun damage, and infection. -Dermis: The second layer of the skin. It contains the body's blood vessels, skin's nerve cells, and sweat glands. -The Subcutaneous Layer: The last layer of the skin. It conatins fat cells that provides insulation for the body.    The body also conatins sweat glands under the surface called exocrine glands that offer two types of protection: -Prespiration: The prespiration cools the skin as it reaches the surface of the skin. -Oil Gland: The oil gland keeps the hair from dryness and keeps bacteria out. *Nail: The nail protects the senstive tip of the fingers and toes. Only two-thirds of the nails are visible. The other third are grown under the nailfold. The nails protects the vulnerable parts of our extremities. *Hair: The hair traps heat within it and helps to keep us warm. It also helps prevent heat loss.