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Shanghai dogs are very special!. There are many dogs in Shanghai Xuhui JTU campus. Hypothesis : Shanghai dogs can read 汉字 ( and obey orders). Result : The clever dog 狗 recognized the label 肉 and ignored the box labeled 菜 Conclusion: At JTU even the dogs are clever.
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There are many dogs in Shanghai Xuhui JTU campus
Hypothesis: Shanghai dogs can read 汉字 (and obey orders)
Result: The clever dog 狗recognized the label 肉 and ignored the box labeled 菜 Conclusion: At JTU even the dogs are clever
What was good? Any problems? What should we learn?
What was good? Good observation Great idea!
Any problems? 鬣狗 hyenas are not dogs How can you find out whether the bacterium that is growing in your flask is the correct one? 老托的故事 I have seen many scientists wasting time because they failed to recognize contaminants.
Any problems? Living things have several senses to ‘read’ the environment List all the senses you know, and the organisms where they are most important. Start with bacteria, give examples. Try to explain without using the dictionary
5 4 3 If you repeat an experiment, make sure that it is a true, independent repeat 2 1 2 2 2 1 1 2
Does a specific mutation increase antibiotic production? Wild-type strain 0 Gene replacements to generate identical mutations Mutant strain 1 Clonal copy of 1 Mutant strain 2 Growing the bacteria (culture broth/medium, flask/fermenter) Measuring antibiotic production (bioassay, LC) A B C D E F G H I K L M mg ml-1 Which values will be most similar (small SD, standard deviation)? Which measurements represent independent repeats? The 3 mutant strains should be the same; why could we get very different measurements?
All the values in Group 1 are dependent on each other because they all go back to mutant 1 • Only measurements from Group 1 measurements from Group 2 qualify as independent repeats Group 1 Group 2 • The values from Group 1 and Group 2 could be very different if one of them had suffered an additional spontaneousmutation. • Additional spontaneous mutations are common if a gene replacement causes the cells to grow slowly because Compensatory mutations may make the strain fitter.