北師大版高中英語模塊7--Unit 21 Lesson2-1
[00:09.67]Exercise 2 Listen to a science lesson.
[00:13.42]Use the strategies to complete the gaps
[00:15.74]in this summary.
[00:22.96]Right, the topic of today's lesson
[00:25.59]is "the brain".
[00:27.92]Well... it is an absolutely amazing organ.
[00:30.55]The brain consists of grey
[00:31.92]and white matter.It weighs just over a kilo-
[00:35.19]just imagine that, like a kilo of potatoes.
[00:38.12]But this is a very special kilo.
[00:40.58]It uses twenty percent of the body's energy.
[00:43.11]And it contains over one hundred billion cells-
[00:45.64]that's a "billion" with a "b".
[00:47.63]One hundred billion cells.
[00:50.81]These make up nerve cells,
[00:52.78]which are connected by electrical impulses,
[00:55.82]The brain sends messages using electrical
[00:58.29]impulses,the same way as a computer works.
[01:01.31]But there are more possible connections in one
[01:04.54]brain than there are more atoms in the universe
[01:07.20]Just think about that again.
[01:08.93]There are more possible connections in one
[01:12.20]brain than there are more atoms in the universe
[01:13.91]
