Skeletal System

Fun Facts Babies have more bones than adults! Both Humans and giraffes have the same amount of bones in their necks. Human thigh bones are stronger than concrete. Your ribs move about 5 million times a year, everytime you breathe! One quarter of the bones in your body, are in your feet!

Functions Support the body Protect organs Allow movement Store minerals Blood cell formation

Types of Joints Immovable Slightly movable Freely movable We have over 230 moveable and semi-movable joints in our body.

Immovable Joints Joints connect bones without allowing any movement. Skull and Pelvis

Slightly Movable The bones are attached by cartilage. These joints allow for a little movement. Spine and Ribs

Freely movable Cavities between bones are filled with synovial fluid. This fluid helps lubricate and protect the bones. Ball and Socket Hinge Pivot Saddle

Ball and Socket Hips Shoulders They allow you to swing your arms and legs in many different directions

Hinge Open and close like a door Elbow and knee Animation

Pivot Rotation of one bone around another Neck and Elbow

Saddle This type of joint allows for back and forth and side to side motion but limited rotation. Thumb

If you are "double-jointed", it just means that you have extra long ligaments in your joints and can bend them farther than usual.