Bones, Muscles and Bones, Muscles and JointsJoints

BonesBones

They provide support for our body and form our general shape

Some bones provide protection for organs, like the skull protecting the brain, or spine protecting the spinal cord

For their weight, bones are very strong

What Are Bones Made What Are Bones Made Of?Of?

Bones have several parts, but are mainly made out of calcium deposits

It takes about 20 years for our bones to completely harden

The building of bones happens throughout our lives

JointsJoints

Joints are where two or more bones meet

They make our skeleton flexible and allow us to move

Types of JointsTypes of Joints

Freely Moveable: Joints with a large range of motion

Partially Moveable: Joints with a limited range of motion. Examples are the vertebrate in your spine

Immovable: Joints that do not move. Examples are in the skull which is made up of several bones fused together

MusclesMuscles

Masses of tough, elastic tissue that pull on bones which cause movement

There are two kinds of muscles: Skeletal Muscle and Smooth Muscle

Muscle TypesMuscle Types

Skeletal Muscle: Muscles that we are able to control and move

Smooth Muscle: Muscles that work without our control. Examples include the heart, stomach, and intestines

Muscles and JointsMuscles and Joints

When muscles contract (get smaller) joints are moved.

Muscles do all of their work when they contract, not when they expand