The Skeletal System Luna Lannoy, Paulina Joo, ValentinaKochian, Isa Lopez Science InstitutoTepeyac 6th Grade
What would happen if humans didn't have bones? You'd be floppy like a beanbag. Could you stand up? Forget it Could you walk? No way Without bones you'd be just a puddle of skin and guts on the floor.
Main functions Skeleton has seven main functions: Support and gives shape to the body. Movement Protects the internal organs Blood cell production Storage Endocrine regulation Provides a base for muscles
Components of the Skeleton • Cartilage and bone form the skeleton. • Cartilage: is flexible and softer than bone. There is cartilage on the end of long bones, in the ears, the nose, and on the ribs; for example. • Bones: are very hard and resistant. Made up of tissues, and minerals like calcium; minerals make bones hard.
Joints • Place were to muscles meet is called a joint. There are two types of joints: fixed joints and movable joints. • Bones connected by fixed joints do not move. For example, there are fixed bones between the bones in the skull. • Bones connected by movable joints can move. Wrist and the union of the pelvis and the femur are examples of movable joints. • Joints allow parts of the body to move. If there weren’t any joints, the skeleton would be rigid. • You have over 230 moveable and semi-moveable joints in your body.
How many bones do humans have? • When you were born you had over 300 bones. • As you grew, some of these bones began to fuse together. The result? An adult has only 206 bones! The axial skeleton (80 bones) is formed by the Vertebral Column (26 bones), the thoracic cage (12 pairs of ribs and the sternum), and the skull (22 bones and 7 associated bones) An adult has only 206 bones!
How do our bones move? • You need muscles to pull on bones so that you can move. • Along with muscles and joints, bones are responsible for you to move. • Your muscles are attached to bones. When the muscle contract, the bones to which they are attached act as levers and cause various body parts to move.
Facts • In an adult the skeleton compromises around 14% of the weight. • Your skull, a series of fused bones, acts like a hard protective helmet for your brain. • The bones, or vertebrae, of your spinal column surround your spinal cord, a complex bundle of nerves. • In an adult the skeleton compromises around 14% of the weight. • The human hand has 27 bones; your face has 14! • The longest bone in your body is your thigh bone, the femur -- it's about 1/4 of your height. • The smallest bone is the stirrup bone in the ear which can measure 1/10 of an inch. • Did you know that humans and giraffes have the same number of bones in their necks? Giraffe neck vertebrae are just much, much longer!