Get to know how each part of the body works through amazing facts and colourful diagrams in this fully updated edition of the bestselling Human Body A Children?s Encyclopedia. Did you know that you are made up of 100 trillion cells? Learn about blood vessels (capillaries, veins, and arteries) which, if they were laid out end to end, would wrap around the Earth twice! Find out what makes a balanced diet - after all, you will eat about 20 tonnes of food in your entire life!