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Corn Reproductive Structures Corn Reproductive Structures Genetics Unit Transparency 2.3 ©2008 The Regents of the University of California Creating a Punnett Square Genetics Unit Transparency 2.4 ©2008 The Regents of the University of California Case Study Summary Sheet Case Study Type of Benefits Risks and concerns Remaining questions Genetic Modification Genetics Unit Transparency 4.1 ©2008 The Regents of the University of California Class Data for Rice Breeding Simulation aromatic, non-aromatic, aromatic, non-aromatic ,flood-tolear nt flood-tolerant flood-intolerant flood-intolerant AAFF AAFf AaFF AaFf aaFF aaFf AAff Aaff aaff Group 1 2 3 4 5 6 7 8 Genetics Unit Transparency 5.1 ©2008 The Regents of the University of California Three Types of Cells Genetics Unit Transparency 6.1 ©2008 The Regents of the University of California DNA base percentages in a variety of organisms Source of A T G C DNA Human 31.0% 31.5% 19.1% 18.4% Mouse 29.1% 29.0% 21.1% 21.1% Frog 26.3% 26.4% 23.5% 23.8% Fruit fly 27.3% 27.6% 22.5% 22.5% Corn 25.6% 25.3% 24.5% 24.6% E. coli 24.6% 24.3% 25.5% 25.6% Genetics Unit Transparency 7.1 ©2008 The Regents of the University of California Matthew Meselson and Franklin Stahl’s Experiment to Investigate DNA Replication First: Scientists James Watson and Francis Crick propose a method of semi-conservative replication in their paper on the structure of DNA. However, they have no data to support their hypothesis. Next: Matthew Meselson and Franklin Stahl use the procedure that follows to investigate DNA created by the process of DNA Replication. Procedure 1. Place bacteria, Escherichia coli (E. coli) in a solution of “heavy” nitrogen. 2. Leave the E. coli in the “heavy” nitrogen solution until all DNA nucleotides, and all DNA strands, are made of “heavy” nitrogen. This is Generation Zero. 3. Isolate the DNA from the E. coli. 4. Place “heavy” DNA in a solution with the same density as DNA. Genetics Transparency 8.1a ©2008 The Regents of the University of California 5. Run “heavy” DNA solution on a centrifuge. A band of “heavy” DNA forms in the test tube. 6. Transfer some of the E. coli with “heavy” DNA into a solution of “light” DNA. 7. Allow the E. coli to reproduce for 20 minutes (the reproduction time of E. coli). 8. Place E. coli in the solution and run the tube on a centrifuge. 9. Analyze the bands of DNA that form. 10. Repeat for 3 rounds of Replication. 11. Compare the bands that form for each round of replication. Genetics Transparency 8.1b ©2008 The Regents of the University of California Results of Meselson and Stahl Replication Experiment Genetics Transparency 8.2 ©2008 The Regents of the University of California Semi-conservative DNA Replication T A A T G C C G Original DNA structuer C G T A C G G C G C C G A T Structuer unzips A T just befoer T A replication A T A T G C G C C G C G A T A T G C Replication er sults G C in 2 new copies of the original DNA molecule C G C G T A T A G C G C Genetics Transparency 8.3 ©2008 The Regents of the University of California Escherichia coli Genetics Unit Transparency 15.1 ©2008 The Regents of the University of California Engineering Genetically Modified Bacteria Genetics Unit Transparency 15.2 ©2008 The Regents of the University of California Transforming Bacteria Genetics Unit Transparency 15.3 ©2008 The Regents of the University of California DNA Electrophoresis Gel Genetics Unit Transparency 16.1 ©2008 The Regents of the University of California .
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