The Skeletal System

	Name		

			

Without a _     __skeleton  _____, our bodies would have no support and would flop. Your skeleton consists of __    206____ bones all linked together. The primary function of the skeleton is to _ support (shape) _ your body and __protect__ the soft organs inside.

The ___   _skull___   _ or __    _cranium_     _ protects your brain like a helmet. The spine is made up of _6 - 33 (depending on how you count them) small bones called _vertebrae_. It is like a flexible chain that keeps you standing straight yet lets you bend. It protects your    spinal_  _cord_, the thick bundle of nerves that connects your body to your brain. The heart and lungs are protected by the _12 pairs (or 24)_ curved bones of the        ribs____. The organs in the lower body are protected by the ____pelvis____.

When we are born our bones are ___       soft      ____ and ___     elastic     ____. Cells gradually deposit __  calcium___   that hardens the bone. An area of specialized cells in the long bones when you are growing taller is called the __      growth_  __  ___   plate    _  __. Bones have a hard white coating but are almost hollow. They are filled with _ marrow__ that makes blood cells.

More than ____  half____ of all our bones are in the hands, feet, ankles, and wrists. Bones meet up with each other at over 100 spots called _   ___joints_____. There are several different types of joints. An example of a ball and socket joint is     hip  (OR)  shoulder   . An example of a ___hinge__ joint is the knee joint. A pivotal joint is the _  wrist  (OR)  ankle  _. Bones are connected together by stretchy cords called ___ligaments___. The ____kneecap____ is the only bone not tied to another by ligaments.

	Many disorders may strike the bones. Two examples of such disorders would be:
__    osteoporosis             ____ and _         arthritis        ___.  (samples only – answers will vary)