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DNA. http://www-personal.umich.edu/~sarhaus/courses/501w98/AUDRA/dna.jpg. What is DNA?. “DNA is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms and some viruses.”
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DNA http://www-personal.umich.edu/~sarhaus/courses/501w98/AUDRA/dna.jpg
What is DNA? • “DNA is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms and some viruses.” • “DNA is often compared to a set of blueprints or a recipe, or a code, since it contains the instructions needed to construct other components of cells, such as proteins and RNA molecules.” http://en.wikipedia.org/wiki/DNA , http://www.ch.cam.ac.uk/magnus/molecules/nucleic/dna1.jpg
What is DNA cont.? • “DNA consists of two long polymers of simple units called nucleotides with backbones made of sugars and phosphate groups joined by ester bonds.” • “Attached to each sugar is one of four types of molecules called bases. It is the sequence of these four bases along the backbone that encodes information.” http://www.ec.gc.ca/EnviroZine/images/DNA.jpg , http://en.wikipedia.org/wiki/DNA
DNA Base Pairing • DNA has 4 bases… • Guanine • Cytosine • Adenine • Thymine • Certain Bases will only pair with one other base… • Guanine & Cytosine • Adenine & Thymine http://www.biologycorner.com/resources/DNA-colored.gif
What is DNA Fingerprinting? • DNA Fingerprinting was developed in 1984, by a British geneticist named Alec Jeffrey's. Variation in peoples DNA was utilized to find individuals. • “The chemical structure of everyone's DNA is the same. The only difference between people is the order of their base pairs.” • “There are so many millions of base pairs in each person's DNA that every person has a different sequence.” • “These patterns are able to determine whether two DNA samples are from the same person, related people, or non-related people.” http://protist.biology.washington.edu/fingerprint/dnaintro.html http://www.umbi.umd.edu/education-outreach/scitech/dnaexplorationstudentpacket.pdf
Restriction Enzymes • A tool scientists use to “digest or cut” DNA at a particular sequence. • DNA restriction analysis is based on two • assumptions: • DNA molecules can be identified by a difference in the sequence of bases • Enzymes, produced naturally by bacteria, cut DNA molecules at specific sites identified by the difference in the sequence of bases. http://www.umbi.umd.edu/education-outreach/scitech/dnaexplorationstudentpacket.pdf
Restriction Enzymes • In the example below, the DNA is cut with the enzyme, HaeIII. Note that the enzyme • cuts only at its particular recognition site (GGCC). http://www.umbi.umd.edu/education-outreach/scitech/dnaexplorationstudentpacket.pdf