Science

Bones

Our bones have two main functions:

Bones protect soft organs in the body
Bones support the body.

Our bones are joined together to form a skeleton.
To keep our bones healthy and strong we need to have lots of calcium.
We find calcium in foods like bread, milk and other foods made from milk like cheese.


There are 206 bones in the body and each one does a very specific job.
You don't have to know them all, only the major ones.
Remember that bones protect and support

The skull
The skull protects the brain

The ribs.
The ribs protect the heart and lungs and other vital organs of the body.

The spine (backbone)
The spine is not really one bone it is lots of little bones that work together to protect the spinal cord. The spinal cord runs from the brain to the base of your spine. The spinal cord is the nerve that sends all the messages to the brain.

The pelvis (hip bones)
The pelvis protects the womb (in females) and the legs join the upper body at the pelvis.

Femur (thigh bone)
This is the biggest bone in your body. This bone runs from your hip to your knee.

We have said that all your bones are joined together to make a skeleton.
However these bones are joined in 3 main ways. They have different types of joints.

Think about the way you can move your lower leg. It will swing backwards and forwards but it will not turn round.
Think of the way you can move you arm it can swing and can move in many directions.
The joint at your knee is different from the way that your arms are jointed.

Question: is there a part of your body that moves like your lower leg?
Go to answer

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


Answer
Your lower arm at the elbow moves in the same way as your lower leg at the knee. It can be straight or bend in.

Both your elbow and knee are called hinge joints.

Hinge joint

 

Your arm (at the shoulder) and your upper leg (at the hip) are both ball and socket joints. 

Ball and socket joint. 

Make a fist and put your other palm around it and see how much your fist can swivel.

We said before that the backbone is not one bone but a number of small bones that work together these are another type of joint. These bones slide over each other. They are sliding joints.

Sliding joints

These bone are little discs (filled with fluid) between them to stop them rubbing.

Well that is it for now, with our quick revision of the bones. There is not very much to remember:

Review

Bones protect soft organs in the body.

Bones support the body.

The major bones in the body are:

3 types of joints link the bones:

Well that is about it for now. You really just have to remember this and you will be okay.
Good luck!

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