1、Unit 1 Great scientists warming up The second suggested absorbed this disease into their bodies with their meals.,Another outbreak hit London.,More than 500 people had died in 10 days.,These numbers in Broad Street near the water pump had many of the deaths,20 and 21 Broad Street and 8 and 9 Cambrid

2、ge Street had no deaths. They didnt drink the water from the Broad Street pump.,These families worked in the pub at 7 Cambridge Street.,16,37,20,8,9,pump,38,40,BROAD STREET,CAMBRIDGE STREET,21,John Snows Cholera Map,7,Pub,What is the problem?,The cholera was the most deadly disease of its day. Neith

3、er its cause, nor its cure was understood.,What caused cholera?,Make a question: Which theory to believe in?,Idea 1,Idea 2,Cholera multiplied in the air without reason. A cloud of dangerous gas would float around until it found its victims.,People absorbed it with their meals.,Which one do you belie

4、ve more? What about John Snow?,A map of Broad Street,What method did he use?,Broad Street,Many deaths happened here.,No death happened here.,It seemed the water from the pump was to blame. What did he do next?,Public house,(Para 6) What was another supporting evidence?,(Para 5) He looked into the so

5、urce of the water,John Snow was able to announce with certainty that polluted water carried the germs.,Read the passage and number these events in the order that they happened.,John Snow began to test two theories.,An outbreak of cholera hit London in 1854.,He announced that the water carried the di

6、sease.,John Snow marked the deaths on a map.,2,1,4,7,Carefulreading:,King Cholera was defeated.,He found that most of the deaths were near a water pump.,He had the handle removed from the water pump.,John Snow investigated two streets where the outbreak was very severe.,3,8,5,6,1. John Snow believed

7、 Idea 2 was right. How did he finally prove it?,KEY: John Snow finally proved his idea because he found an outbreak that was clearly related to cholera, collected information and was able to tie cases outside the area to the polluted water.,Read and answer the questions.,2. Do you think John Snow wo

8、uld have solved this problem without the map? Give a reason.,KEY: No. The map helped John Snow organize his ideas. He was able to identify those households that had many deaths and check their water- drinking habits. He identified those houses that had no deaths and surveyed their drinking habits. T

9、he evidence clearly pointed to the polluted water being the cause.,3. Cholera was a 19th century disease. What disease do you think is similar to cholera today?,KEY: Four diseases, which are similar today, are SARS, AIDS, TB(肺結(jié)核) and bird-flu, because they are very serious, have an unknown cause and need public health care to solve them.,What should we pay attention to in our daily life in order not to get infected with cholera?,Heat the food left overnight,Cook raw food thoroughly,Wash hands often,Keep away from flies,choose fresh se