Genetic Engineering STS Biology Unit 4 Genetics Mrs. Stein
What is Genetic Engineering?Manipulating DNA for practical purposes:– DNA sequencing and the Human Genome– Transgenic organisms have many applications in agriculture– DNA fingerprinting used in forensics
Genetic Engineering Tools: PCRPolymerase chain reaction (PCR) uses DNApolymerase to make many copies of DNAGives scientists enough DNA to work with!
Genetic Engineering Tools: Restriction EnzymesProteins whichrecognize and cutspecific base sequencesin DNAResults in fragments ofDNA with “sticky ends”First step in many DNAmanipulations
PlasmidsPlasmids – circular DNA molecules in manybacteria
Plasmid use in genetic engineering
Recombinant DNA and Plasmids Genes are “spliced” into plasmids Recombinant DNA –contains DNA from different sources Plasmids containing the target gene are reproduced (cloned) inside bacteria Used to make various proteins: – insulin, human growth hormone, pest resistance proteins in plants
Gel Electrophoresis DNA digested by restriction enzymes Power source Longer DNA fragments Shorter DNA fragmentsDNA fragments Gelare placed in DNA is negativelywells of the gel charged so it will migrate to the positive size
DNA FingerprintingAnalysis of gelelectrophoresis tocompare the genomes oforganismsUsed in crimeinvestigations andpaternity tests
Whose kids are these???Using the gel, determine:– Which child/children are the offspring of both mom and dad?– Which child/children are the dad’s child from another marriage?– Which child/children are the dad’s child from another marriage?– Which child/children are adopted?