Presentation on theme: "Ch. 13.4: DNA Technology Applications"— Presentation transcript:
1 Ch. 13.4: DNA Technology Applications Objectives:Describe the technique that enables scientists to mass-produce specific segments of DNA in a test tube.Describe a technique used to compare DNA samples.VocabularyPCRGel electrophoresisGenetic MarkerDNA fingerprint
2 PCR Polymerase Chain Reaction Technique used to MAKE COPIES of a SEGMENT OF DNA.Start with 1 microgram DNA --> billions of copiesNeed enough DNA to analyze.
3 PCRIngredientsPRIMERS (short strands of DNA that will pair w/ target sequence)NucleotidesDNA Polymerase
4 PCR Steps 1. Add heat to separate strands. 2. Cool & add primers 3. Primers bind to target strand.4. DNA polymerase adds nucleotides.
5 Comparing DNA Gel Electrophoresis Sorts molecules or fragments of DNA BY LENGTH.Used to compare DNA fr. different people.
6 Gel Electrophoresis DNA is (-)charged. DNA fragments move thru. gel to (+) end of gel bed.Shorter fragments travel farthest.
8 DNA FingerprintingPattern of DNA fragments produced by restriction enzymes.Each person has unique patternsCompare genetic markers between samples.Genetic Markers =Stretches of DNA that are variable among individuals.Differences due to different alleles, mutations in intron sequences
9 SummaryPCR -->Make copies of DNA from a drop of blood or hair follicle.Gel electrophoresis -->Separate fragmentsDNA fingerprinting -->Look for genetic markers to identify. Each person has unique DNA sequence = different fragments = diff. banding pattern (Fingerprint)