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A test recording the amount of electrical activity in the brain
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A. Skim the article. Match the titles to the paragraphs A-C.
1. Exercise helps make you smarter.
2. When you learn, you change the structure of your brain.
3. Neurons can send information to your brain extremely quickly.
B. Skim the article. How does the brain send messages to other parts of the body?
C. Look at the title. Why do you think your brain is "amazing"? What are some things your brain helps you do?
YOUR AMAZING BRAIN
You carry a 1.3-kilogram mass of fatty material in your head that controls everything your body does. It lets you think, learn, create, and feel emotions. What's this amazing machine? It's your brain!
A
Your brain contains about 100 billion tiny cells called neurons. If a bee lands on your foot, sensory neurons in your skin send this information to your brain at a speed of more than 240 kilometers per hour. Your brain then uses motor neurons to send a message back to your foot: Shake the bee off quickly! Motor neurons can send this information at more than 320 10 kilometers per hour.
B
Riding a bike seems impossible at first, but you can soon master it. How? As you practice, your brain sends "bike riding" messages along certain neural pathways again and again, forming new connections. In fact, the structure of your brain changes every time you learn.
C
Your body produces a chemical after you exercise that makes it easier for your brain to learn. So, if you're stuck on a homework problem, go out and play soccer, and then try the problem again. You might discover that you're 20 able to solve it!
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