Define selective breeding. Define pure breeding. Define domestication relative to the examples above.

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1 Define selective breeding. Define pure breeding. Define domestication relative to the examples above. Selective Breeding

2 Selective Breeding Induced nondisjunction Define hybridization. Explain how hybridization has been used in agriculture, listing a number of desirable traits and tomatoes as an example. The diagram at right is a complex example of how hybridization, along with other techniques, can be used to create entirely new plant species! What is the typical result of hybridization between closely related animal species? What are some examples?

3 Define inbreeding, including why it is often done in selective breeding. What is often the result of excessive inbreeding and why? Define population bottleneck. Explain how a population bottleneck in the distant past may explain why Cheetahs today show little genetic variation. What is the danger of low genetic diversity in natural populations? Selective Breeding

4 Increasing Variation What is the ultimate source of genetic diversity (new genes), and what are the two major types? How has this been used to produce organisms with unique, desirable traits? Give one bacterial example. Define polyploidy. Explain how the induction of the polyploid state has been used in agriculture using the strawberry as an example. What desirable characteristics do polyploid plants sometimes poses? What is the usual result of polyploidy in animals?

5 Define genetic engineering. Define DNA extraction. What are possible sources for DNA extraction? Refer to the diagram to understand how DNA is extracted... What common household substance is in the cell lysis buffer and explain why it works. What is protease and what does the protease/salt solution do? What about protease requires the solution to be incubated at 50oC? Define precipitate in this context. What about ice-cold alcohol causes DNA to precipitate from the solution? Tools: DNA Extraction

6 Define polymerase chain reaction (PCR). Review: What natural process is PCR similar to? List the 4 ingredients for PCR. Explain what the DNA primers do and are for? What is thermocycling and what does it do? Use the smaller diagram at right to more fully label the steps and thermocycles in the diagram above. Be able to explain what PCR does and how it works. Tools: PCR

7 Tools: Restriction Enzymes Recognition sequences DNA sequence Restriction enzyme EcoR I cuts the DNA into fragments Sticky end Define restriction enzyme. Where do they come from and how do they function in that organism? Define recognition sequence. Define restriction site and label them in the diagram. Explain how restriction enzymes can result in DNA fragments with sticky ends. How is this useul?

8 Tools: Gel Electrophoresis Power source DNA plus restriction enzyme Longer fragments Shorter fragments Mixture of DNA fragments Gel Define gel electrophoresis. How is the DNA obtained and treated prior to running on a gel? What is the gel made of and what are its properties? What is the purpose of the power source and electrodes at either end of the gel? Refer to the diagram to explain how each step is performed, how it works, and how results are analyzed. What are possible sources of DNA samples for this analytic tool and what comparisons can be made?

9 What can be learned by sequencing DNA? Review: What natural process is DNA sequencing similar to? Tools: DNA Sequencing DNA strand of unknown sequence (pretend) Define didioxynucleotide. Where do they come from? How many kinds are there and what is attached to each? Dye molecules List the 5 ingredients for DNA sequencing. Refer to the diagram to explain how this process results in a mixture of DNA fragments of DNA fragments different length, each labeled with one synthesized using fluorescent dye molecule. What process that you know of is capable of separating the different length fragments? unknown strand as a template

10 Tools: DNA Sequencing Review: What process is shown in the diagram? Refer to the diagram to explain how this process is separating the different length fragments that resulted from the process shown on the previous slide. Refer to the diagram to explain how the results of this process indicate the sequence of the original unknown DNA strand on the previous slide. Electrophoresis gel

11 Review: Define/know the following... bacterial plasmid, bacterial transformation (Remember Griffith?), restriction enzyme, sticky ends, gene expression. Define gene donor. Also be aware that genes can be artificially synthesized. Define green florescent protein (GFP). Define DNA ligase. Define recombinant DNA. Define transgenic. Refer to the diagram at right and use your background knowledge to explain how to engineer recombinant DNA and use it to create transgenic bacteria that express GFP (above photo). Why do this? Tools: Recombinant DNA

12 Transforming Bacteria Recombinant DNA Gene for human growth hormone Gene for human growth hormone Human Cell Bacterial chromosome Sticky ends DNA recombination DNA insertion Bacteria cell Plasmid Bacteria cell expressing the gene for human growth hormone Compare this diagram with that on the previous slide. Other than color and greater detail, what is the most exciting difference? Problem: Transformation is not 100% efficient and you can t directly see the genes inside an organism. Genetic engineers need to be able to distinguish between bacterial cells that have vs. have not been transformed. Define genetic marker. What gene that you know of could be used as a genetic marker? Why? Generally, what kinds of genes have been used to genetically modify (GM) bacteria? Why?

13 Gene to be transferred Agrobacterium tumefaciens Cellular DNA Marker Gene Recombinant plasmid Transforming Plant Cells Transformed bacteria introduce plasmids into plant cells. Inside plant cell, Agrobacterium inserts part of its DNA into host cell chromosome. Complete plant generated from transformed cell. Plant cell colonies Review: What tool that you know of is used to create the recombinant plasmid with the gene(s) to be transferred? What process that you know of makes it possible to get the recombinant plasmid into Agrobacterial cells? What makes it possible to know which cells have been successfully transformed? What makes Agrobacterium tumefaciens suitable for transforming plant cells? How can a complete plant develop from just one or a few transformed somatic cells? What are two other methods for transforming plant cells? Generally, what kinds of genes have been used to genetically modify (GM) plants? Why?

14 Transforming Animal Cells Recombinant DNA New gene + Marker gene Flanking homologous sequences New gene(s) replace(s) target gene Target gene Host Cell DNA to be modified Review: What tool that you know of is used to create the recombinant DNA with the new gene(s) to be transferred? What process, also used to transform plant cells, is most often used to get the recombinant DNA into the nucleus of the cell to be transformed? What makes it possible to know which cells have been successfully transformed? Can a complete animal develop from just one or a few transformed somatic cells, as in plants? On what kind of cell is this procedure usually performed? Once in the nucleus, explain how the new gene(s) may replace the target gene? (Hint: This is similar to a process that allows segments of DNA to be exchanged between homologous chromosomes during meiosis.) Generally, what kinds of genes have been used to genetically modify (GM) animals? Why?

15 Cloning Define clone in context to biology. What did Ian Wilmut succeed in doing for the first time in 1997? What other kind of animals had been cloned before this time? Why do you think they were easier to clone? What are some reasons for creating clones? Dolly and Bonnie (Dolly's 1st offspring)

16 Cloning Donor Somatic Cell Nucleus Zygote Egg Cell Embryo Dolly Cloned Lamb Foster Mother What is this method of cloning called? Refer to the diagram to make a detailed, step-by-step list of this method for producing a clone using proper terminology. Why did Wilmut use a white-faced sheep as the nuclear donor and black-faced sheep as the egg cell donor and foster mother? What other mammals have been successfully cloned? Are there cloned humans?