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Aztecs, Incas, and Mayas They made mummies.^93 Inca gold The Incas made objects from gold. The Spanish greed for gold led to the ...

What was chain mail? History of people 94 The Red Fort in India was a palace with stone walls 30 m (100 ft) tall. Norman keeps w ...

Knights and castles Armour made from small loops of metal.^95 Knights Knights were soldiers who fought on horseback. They wore h ...

Who was the first person to go into space? And when? History of people 96 The 20th century was the time from 1901 to In the 20t ...

20th century A Russian cosmonaut (astronaut) called Yuri Gagarin in 1961.^97 Pop music The Beatles were one of the most successf ...

What do we call the study of the human body? Human body 98 The greatest machine you’ll ever own is your body. It’s more complica ...

Your amazing body Anatomy.^99 Being human Although we look different from animals, our bodies are similar on the inside. Our clo ...

How many genes are there in each cell in the human body? Human body 100 All human bodies work the same way, but everyone is diff ...

What makes you you? About 30,000 specific genes.^101 DNA Your genes are stored in a chemical called DNA, which looks like a twis ...

How many cells are there in the human body? Human body 102 Every part of your body is made of tiny building blocks called cells, ...

Building blocks About 100 trillion.^103 Fat cells are bubble shaped. They store fat under your skin. Many blood cells are red. T ...

Which body system makes your stomach rumble? Human body 104 Your cells and tissues are organized into larger body parts called o ...

Organizing the body The digestive system.^105 Breathing system: the main organs are your lungs, which take in air. Hormone syste ...

106 You would be like a lump of jelly without your skeleton – a frame of bones that holds you up and protects your internal orga ...

107 Muscle magic Muscles are rubbery, stretchy straps. You can control some of your muscles, like the muscles in your arms and l ...

Do clever people have bigger brains? Human body 108 Your brain is the part of your body that makes you think, feel, and remember ...

Brain and senses No. Everyone’s brain is about the same size.^109 Skin and touch Nerves in your skin tell you if things feel har ...

Breathing How many breaths do you take in a day? Human body 110 We have to breathe all the time in order to supply our bodies wi ...

Breathing About 23,000.^111 Windpipe Air from your mouth and nose enters your windpipe, which goes down your throat into your ch ...

How many dead-skin flakes fall off every day? Human body 112 All about skin Two layers Your skin has two main layers. The top on ...