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DNA Technology. Ethics of Genetic Engineering. Rate from 1 (no) to 5 (yes) for these potential advances. Describe one pro and one con for each advance. Transgenic Organisms. Difficulties with DNA. There are often thousands of genes on a DNA molecule Electrophoresis
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Ethics of Genetic Engineering Rate from 1 (no) to 5 (yes) for these potential advances Describe one pro and one con for each advance.
Difficulties with DNA • There are often thousands of genes on a DNA molecule • Electrophoresis • One cell normally provides too little material for study • Polymerase Chain Reaction (PCR) • Gene cloning
AATTCGGCCATATACG GCCGGTATATGCTTAA Desired Gene Target Sites for EcoRI Restriction Enzymes • Bacterial defense against viral DNA • Excise DNA at specific sequences CCTTTG AATTCCCAGAATC GGAAACTTAA GGGTCTTAG
Electrophoresis • Separation of molecules based on size • Negatively charged DNA molecules are pulled through a gel by an electrical field • Smaller molecules travel faster and farther
Restriction Fragment Length Polymorphisms (RFLP’s) AAGAATTCCCTGATCCATATATATATATCGGATCTAGAATTC TTCTTAAGGGACTAGGTATATATATATAGCCTAGATCTTAAC AAGAATTCCCTGATCCATATATCGGATCTAGAATTC TTCTTAAGGGACTAGGTATATAGCCTAGATCTTAAC Variations in DNA Variations in fragment sizes Variations in electrophoresis bands
Poop Cujo Jordan
Restriction Mapping Uncut plasmid Cut with EcoRI Cut with BamH3 Cut with Both DNA Marker 10 8 6 4 2 (kilobases)
Using Radioactive Probes Each well contains a sample Probe is complementary to desired gene An impression is made Adhered probe leaves dot on radiosensitive film Radioactive probes applied
Intron Elimination Eukaryotic mRNA Complementary DNA (cDNA) Intron
Polymerase Chain Reaction • In vitro amplification of a select length of DNA Denaturation Priming Elongation Desired Gene