Skeletons are made out of bones that have cells that take in nutrients and use energy.
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The skeletal system is the frame work of your body and has 5 major functions:


-Give shape and support.
-Protect internal organs.
-Help muscles move.

-Produces blood cells.
-Calcium and phosphorous are stored in the skeleton.

-skeletal system= It is all the bones in the body
-Periosteum=Its a tough, tight-fighting membrane that covers a bones surface and contains blood vessels that transport nutrients into the bone.
-Cartilage=Tough, flexible tissue that joins vertebrae and makes up all or part of the vertebrate endoskeleton.
-Joint= Any place were two or more bones come together.
-Ligament=Tough band of tissue that holds bones together at joints.

A tough membrane called periosteum covers a bone and supplies nutrients to it. Small blood vessles in the periosteum carry nutrients into the bone. Under it are two different types of bone tissue--compact bone and spongy bone.
Compact bone is a hard stronger layer under the periosteum, it gives bones strength. Bone cells and blood vessels are also found in this layer.
Spongy bone is lightwieght and located towards the end of long bones.The ends of bones are covered with a smooth, slippery,thick layer of tissue called cartalige

Bone Formation
Osteoblasts are bone-forming cells and osteoclasts are cells that break down bones´╗┐.Osteoblasts deposite the minerals calsium and Phosphorus in bones, making the bone tissue hard.Osteoclasts breaks down bone tissue in other areas of the bone, this usually happens in a healthy person.
A joint is any place were 2 or more bones come together, bones are held in place at these joint by at tough band of tissue called a ligament. There is 2 types of joints, immovable joints - it allows little or no movment to the joint- is found on the skull, and movable joints which is the most common one. There's different types of movable joints:
  • Pivot joint --> arm
  • Hinge joint --> Knee
  • Gliding joint --> Vertebrae
  • Ball-and-socket joint --> Shoulder