The bones are the framework of the body, working with muscles and joints to hold our body together and support freedom of movement.
What Is Bone?
Bone is living, growing tissue made up of three major components: collagen (provides a soft framework of bone), calcium phosphate (adds strength to bone), and living bone cell (removes and replaces weak parts of the bone). The five main functions of bones are support, movement, protection, production of blood cells, storage of minerals, and endocrine regulation.
Bones by the Numbers
White Blood Cells
5 Types of Immune Cells: Basophils, eosinophils, lymphocytes, monocytes, and neutrophils
3 Ways They Protect: Ingesting foreign materials and debris, destroying infectious agents, and producing antibodies
1 Goal in Mind: Keep the body safe and healthy
Protect Your Bones
Prevention Is Key to a Lifetime of Good Bone Health
Building strong bones and maintaining good bone health when you are young helps prevent bone loss as you age.
Structure of a Joint
Joints are held together and supported by tough bands of connective tissue called ligaments. Smooth cartilage, which is made of collagen, prevents friction as the bones move against one another. In freely movable joints, the entire joint is enclosed inside a membrane filled with lubricating synovial fluid, which helps to provide extra cushioning against impact.
6 Types of Joints in Your Body
Ball and Socket Joint: In this joint, the rounded head of one bone sits within the cup of another. Movement in all directions is allowed. Your hip and shoulder joints are good examples.
Saddle Joint: This joint allows movement back and forth and side to side but does not allow rotation. The joint at the base of both of your thumbs is a saddle joint.
Hinge Joint: This joint opens and closes in only one direction like a door hinge. Your knee and elbow joints are good examples.
Condyloid Joint: A joint like this permits movement without rotation. Your jaw and finger joints are good examples.
Pivot Joint: In this joint, one bone swivels around the ring formed by another bone. You’ll find this joint between the first and second vertebrae of your neck.
Gliding Joint: Also called a plane joint, this joint features smooth surfaces slipping over one another, allowing limited movement. Your wrist joints are good examples.
Bone & Joints
Good Information to Know