This base-catalyzed isomerization involves the following steps: 1. Deprotonation to form tetrahedral intermediate 1; 2. Collapse of the tetrahedral intermediate and bond cleavage to form enolate ion 2; 3. Proton transfer to form enolate ion 3; 4. Intramolecular aldol reaction to form tetrahedral intermediate 4. Write out the reaction on a separate sheet of paper, and then draw the structure of enolate ion 3

2positives of biotechnology: 1. plants have become more resistant to viruses and other communicable pests.2. with the of biotechnology, we have been able to produce better tasting fruits as well as vegetables.2 negatives of biotechnology: 1. biotechnology poses a number of environmental threats. genetically modifies crops often infect monarch butterflies and other insect species.2. viruses could combine with crops.