第1章 Lesson 1 The Amazing Brain

We carry around a mass of wrinkly material in our heads that weighs more than a kilogram. It controls everything we do from thinking and learning to feeling emotions and breathing. This incredible structure is your brain.

If, for example, a cup is going to fall off the counter and you have only seconds to react, your brain quickly processes the signals coming from your eyes. It calculates how fast you will need to move in order to catch it before it falls and smashes on the floor. No computer can perform such a complex process.

Your brain contains over 100 billion microscopic cells called neurons. That is so many that it would take over 3000 years to count them all. Whenever you dream, think, or move, it it because of tiny electrical signals racing between these neurons between billions of neuron highways. Your neurons create and send more messages than all the phones in the entire world.

Sensory neurons on your skin can relay information to your brain at speeds of over 240 kilometers per hour. If your hand touches something very hot or a bee lands on your skin, very high speed is needed to deal with these situations.

The act of learning changes the structure of your brain. When you learn to ride a bike, your brain sends bike riding messages along certain pathways of neurons, forming new connections.

It is a well-known fact that exercise makes your heart beat faster. Sports such as running and playing soccer are good for your body, and can also improve your mood. Additionally, scientists have recently learned that for a period of time after exercising, your brain is actually more receptive to learning. So, if you're having trouble completing your homework, maybe you should go jogging or play a game of tennis. It might improve your brain power.

I. Word List

wrinkly: not smooth

complex: complicated, not simple

receptive: open to and able to do things

II. Reading Skills—Answer the following questions.

1. What are the microscopic cells that send messages to your brain called?

___________________________________________________________.

2. What happens every time you learn something new?

___________________________________________________________.

3. Why is exercise good for you?

___________________________________________________________.

4. What should you do if you are having a hard time learning something?

___________________________________________________________.

5. Why is your brain better than a computer?

___________________________________________________________.

III. True or False—Read these sentences carefully. Write T (true) or F (false) for each one.

___ 1. Our brains weigh less than one kilogram.

___ 2. We can easily count the number of neurons in our brain.

___ 3. We can see neurons with our eyes.

___ 4. We can learn better before exercising.

___ 5. Exercise can help our brain function better.

IV. Fill in the blanks—Read these sentences carefully and fill in the blanks with words from the reading.

1. The brain is a very complicated s _ _ _ _ _ _ _ _.

2. The brain can p _ _ _ _ _ _ a lot of information.

3. Exercise makes the heart b _ _ _ faster.

4. Sensory neurons are found on the s _ _ _.

5. There are e _ _ _ _ _ _ _ _ _ signals in our brains.