试题详情
阅读理解-阅读单选 0.85 引用3 组卷55

You carry 1.3 kg fatty substances in your head that controls everything you will ever do. This fantastic control center lets you think, learn, create, and feel emotions. It also controls everything your body does. What is this amazing machine? It’s your brain — a structure so amazing that the famous scientist James Watson called it “the most complex thing we have yet discovered in our universe”.

Imagine your cat jumps onto the kitchen counter, and is about to step onto a hot stove. You would have only few seconds to act. In situations like this, your brain reads the signals from your eyes and quickly calculates when, where and at what speed you need to run to save her. Then it tells your muscles to move. No computer can match your brain’s great ability to download, process, and react to the flood of information from your eyes, ears and other sensory organs.

If a bee lands on your foot, sensory neurons (感觉神经元) 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 (运动神经元) to send a message back to your foot: Shake the bee off quickly! Motor neurons can send this information at more than 320 kilometers per hour!

Your brain has about 100 billion tiny cells: neurons — it would take you more than 3,000 years if you tried to count them all. Whenever you dream, laugh, think, see or move, tiny chemical and electrical signals are racing between these neurons along billions of tiny neuron pathways. Believe it or not, the activity in your brain never stops. Countless messages fly around inside it every second, like a super-fast game of table tennis. Your neurons create and send more messages than all the phones in the entire world. And although a single neuron produces only a tiny amount of electricity, all your neurons together can produce enough electricity to power a light bulb.

【小题1】What does “the most complex thing” mean?
A.A supercomputer.B.The universe.
C.Human brains.D.Our emotions.
【小题2】What can we know from the passage?
A.Brains can download more information than any computer.
B.The cat plays an important role in testing human brainpower.
C.Motor neurons in human brains serve to send countless messages.
D.Your brains can use neurons to send messages back faster than bees’.
【小题3】The author mentions “to power a light bulb” in Para. 4 to show ________.
A.neurons can send lots of messages
B.how many active tiny cells the brain have
C.how much electricity the brain can produce
D.there is countless information in the brain
【小题4】What is the main idea of the passage?
A.The powerful brain is a wonderful machine.
B.Brains work well in controlling body movements.
C.The brain is the most complex structure in the universe.
D.Human brains are made up of numerous neurons.
19-20高一上·全国·单元测试
知识点:身体部位 科普知识 答案解析 【答案】很抱歉,登录后才可免费查看答案和解析!