Interactive exercises:

• Click here to try an interactive exercise on naming the bones

• Click here to try an interactive exercise on dragging the labels into the correct positions

Information on the Human Skeleton:

Functions of the skeleton:

1. Support: The skeleton provides the framework to keep the human body in the correct shape, by supporting many internal organs and the muscles of the body.

2. Protection: Important and delicate organs are protected by bone. Examples include the skull protecting the brain and eyeballs, the ribs protecting the heart and lungs, and the vertebral column protecting the spinal cord.

3. Movement: Joints between the bones allow movement to be smooth, without friction.  Muscles can only exert a pulling force so they are often arranged in pairs, one muscle producing the opposite movement of the joint to the other muscle.  The bones and joints are often arranged as levers so a small contraction in the muscle produces a large movement in the bones.

4. Attachment: The bones of the skeleton provide an attachment surface for muscles, tendons and ligaments. Without these attachments, the movement referred to above would not occur.

5. Blood cell production: blood cells are produced in the red bone marrow inside the larger bones of the body.

Questions and answers about bones:

How many bones are there in the human body?

• The adult human skeleton is made up of 206 bones.  A baby is actually born with about 300 bones but many fuse together as it grows up.

How do bones change as a human grows?

• In the human embryo the entire skeleton is made of cartilage, a firm but elastic material (in an adult, cartilage supports the ear).  Cartilage is made up of tough non-elastic fibres called collagen, mixed with stretchy elastic fibres. 

• Gradually the bones develop by depositing a hard mineral called calcium phosphate.  This is called ossification. The final bone is made up of this mineral and the tough collagen fibres.

Why is bone made up of two completely different materials?

• If bone did not have the collagen fibres in it then it would be too rigid and would shatter very easily.

• If bone did not have the minerals in it then it would be too flexible and could not support and protect other parts of the body.

How do male and female skeletons differ?

• Adult males and females have slightly different skeletons. Male skeletons have slightly thicker and longer leg and arm bones while female skeletons have a wider pelvis and a larger space within the pelvis to allow a baby to travel through more easily at birth.

How can broken bones repair themselves?

• Bone is a living material and can repair itself when it is broken or fractured.  Small bones such as the ribs can repair themselves quickly but a large bone such as a femur can take a long time.

What can weaken bones?

• If a child's diet is low in calcium or vitamin D then the bones will grow but ossification is not completed. The adult bones are deformed and weak so they fracture easily.  This deficiency disease is called rickets.

• Many women suffer from osteoporosis after the menopause.  This is where the amount of mineral in the bone decreases so the bones are weakened.