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9.1 Manipulating DNA Set up Cornell Notes on pg. 15 Topic: 9.3 DNA Fingerprinting Essential Question: 1.Describe two ways in which DNA fingerprinting is used. 2.1 Atoms, Ions, and Molecules 9.3 DNA Fingerprinting 1.Describe two ways in which DNA fingerprinting is used. KEY CONCEPT DNA fingerprints identify people at the molecular level
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9.3 DNA Fingerprinting KEY CONCEPT DNA fingerprints identify people at the molecular level.
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9.3 DNA Fingerprinting REVIEW from 9.1 Gel electrophoresis is used to separate DNA fragments by size. –A DNA sample is cut with restriction enzymes. –Electrical current pulls DNA fragments through a gel.
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9.3 DNA Fingerprinting A DNA fingerprint is a type of restriction map. DNA fingerprints are based on parts of an individual’s DNA that can be used for identification. –based on noncoding regions of DNA that have repeating DNA sequences –number of repeats differs between people
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9.3 DNA Fingerprinting A DNA fingerprint is NOT actually a fingerprint ! X X
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9.3 DNA Fingerprinting DNA fingerprinting is used for identification. DNA fingerprinting depends on the probability of a match. –Many people have the same number of repeats in a certain region of DNA. –The probability that two people share identical numbers of repeats in several locations is very small. (mother) (child 1) (child 2) (father)
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9.3 DNA Fingerprinting Children share some bands with both parents
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9.3 DNA Fingerprinting DNA Fingerprinting Video
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9.3 DNA Fingerprinting –Individual probabilities are multiplied to find the overall probability of two DNA fingerprints randomly matching. –Several regions of DNA are used to make DNA fingerprints. 1 1 1 1 500 90 120 5,400,000 1 chance in 5.4 million people to have the same DNA fingerprint xx = = 1 in every 500 people has 3 copies in location A 1 in every 90 people has 6 copies in location B 1 in every 120 people has 10 copies in location c
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9.3 DNA Fingerprinting DNA fingerprinting is used in several ways. –evidence in criminal cases –paternity tests (Who da’ Daddy???) –immigration requests –studying biodiversity – tracking genetically modified crops
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9.3 DNA Fingerprinting DNA Evidence Video
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No Electronics At School! Who Broke The Rule? Gel Electrophoresis A DNA Fingerprinting Simulation
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Today’s Task Today you will work with 2 partners to perform a lab simulation based on a scenario in which you are to identify the owner of an electronic device left in a classroom and subsequently claimed by four different students. This activity will model the processes of gel electrophoresis and DNA fingerprinting Let’s get started!!
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Procedures Begin by reading the scenario and discussing it with your partners. Be sure you understand the problem. Get the materials needed to complete the activity.
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Procedures Use the chart paper provided by your teacher to make a larger version of the gel electrophoresis chamber. Use a ruler or meter stick to make sure all of the lengths are the same. Use “Who Ate the Cheese” as a model
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Who Broke the Rule? Materials Needed: –Scissors –Ruler –Chart Paper –DNA Samples (5) –Glue Stick –Bio Book (266-267) –Charge (+/-) –Title –Color –Circle the person who broke the rule!!!! 16 REMEMBER to cut @ CCGG CC GG
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Procedures Examine each DNA fragment strip closely, looking for the sequence CCGG. This is a restriction site, where enzymes will cut the DNA into even smaller fragments. Use a pencil to mark these sites, with a line between the inner C and the inner G ( CC│GG ). Then use the scissors to cut across the fragments at those sites. Count and label the number of base pairs contained in each of the DNA fragments. Look at each DNA fragment carefully, looking for the sequence CCGG. This is a restriction site, where enzymes will cut the DNA into even smaller fragments. Count and label the number of base pairs contained in each DNA fragment.
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