Unit 21 Human BiologyLesson 2 Brain PowerMatch the key words with the definitions.Key wordsatom, billion,cell,nerve cell,organ1.one thousand million2.a part of the body that has a particular purpose, e.g.the heart,the liver3.the smallest piece of sth that can exist alone4.a tiny part of the body that helps carry messages to and from the brain5.a unit of living matterbillionorgancellNerve cellatomListening strategies: completing a text1.Before you listen,read the text and predict what kind of information you need. remember you may need more than one word2.Underline some important words in the text before each gap. 3.While you are listening,listen for these important words ---the information you need should follow them 4.You can complete the gaps using abbreviations at first— this saves time. Then write them in full.Listen to a science lesson.use the strategies to complete the gaps in this summary Exercise 2The brain consists of grey and (1) matter. It weighs(2) .It uses (3) of the body’s energy. It contains over (4) which make up nerve cells. These nerve cells are connected by electrical impulses. There are more possible connections in one brain than there are (5) . Scientists have mapped different areas of the brain which are responsible for (6) .The area of the brain related to controlling(7) could be compared to miniature film studios. Our eyes and ears send signals(8) , and it is our brain that interprets these signals and builds up a picture of the outside world. Scientists have also identified areas responsible for different emotions,such as(9) , love and laughter. There are also different areas for different types of thinking, such as learning your own language and learning a (10) language....