Period 5(Section B 3a－Self Check)一、阅读理解/Your brain controls everything you do. It makes it possible for you to think, learn, create and feel; to blink(眨眼) and breathe and for your heart to beat—this fantastic control center is your brain. It is so amazing that a famous scientist once called it “the most complex(复杂的) thing we have yet discovered in our universe”．Can this small grey organ(器官), which weighs less than one and a half kilos, really do so much? Amazingly, your brain contains about 100 billion neurons(神经元)—it would take you over 3，000 years to count them all. Believe it or not, the activity in your brain never stops. Your neurons create and send more messages than all the phones in the world. And although one neuron creates only a little electricity, all your neurons together can produce enough electricity to power a light bulb(灯泡)．So exactly how fast does your brain work? Well, imagine this: A bee lands on your foot. Neurons in your skin send this information to your brain at a speed of more than 240 kilometers per hour. Your brain then uses other neurons to send the messa |
