Chapter 13 Genetic Engineering Changing the Living World (pp. 319-321) Manipulating DNA (pp. 322-326) Cell Transformation (pp. 327-329) Applications of Genetic Engineering (pp. 331-333) Updated March 2006 Created by C. Ippolito May 2005

Chapter 13 Section 1 Changing the Living World Objectives: Describe two techniques used in selective breeding Explain the purpose of selective breeding Tell why breeders induce mutations Updated March 2006 Created by C. Ippolito May 2005

Selective Breeding Allowing organisms with desired characteristics to produce the next generation. Domestic animals Crop plants Luther Burbank – potato resistant to blight Hybridization – crossing dissimilar individuals to combine the best of both Inbreeding – continued breeding of individuals with similar characteristics Risk of developing genetic defects Most “pure” breeds of dogs have some medical “problems” Updated march 2006 Created by C. Ippolito May 2005

Hybrid Breeds Whoodle Doodleman Updated march 2006 Created by C. Ippolito May 2005

Pure Breeds Samoyed Papillon Updated march 2006 Created by C. Ippolito May 2005

Increasing Variation Breeders can increase genetic variations by inducing mutations Mutagens – increase chance of spontaneous mutations Chemicals Radiation Oil eating bacteria Polyploidy in plants extra sets of chromosomes Updated march 2006 Created by C. Ippolito May 2005

Chapter 13 Section 2 Manipulating DNA Objectives: Explain how scientists manipulate DNA Updated March 2006 Created by C. Ippolito May 2005

Genetic Engineering Making changes in the DNA code of living organisms: DNA extraction – remove DNA from cells Cutting DNA – restriction enzymes look for specific bases and cut DNA into pieces Separating DNA – gel electrophoresis separates DNA pieces by size Small fragments move farther than large fragments Updated march 2006 Created by C. Ippolito May 2005

Restriction Enzymes Updated march 2006 Created by C. Ippolito May 2005

Gel Electrophoresis Patterns can be used to identify individuals Updated march 2006 Created by C. Ippolito May 2005

DNA Sequencing different enzymes used to cut DNA Identify order of bases Now done by automated computer process Updated march 2006 Created by C. Ippolito May 2005

Polymerase Chain Reaction PCR allow multiple copies making sequencing even easier Updated march 2006 Created by C. Ippolito May 2005

Chapter 13 Section 3 Cell Transformation Objectives: Summarize what happens during transformation Explain how you can tell if a transformation experiment has been successful Updated March 2006 Created by C. Ippolito May 2005

Cell Transformation cell takes in DNA from outside the cell. external DNA becomes part of the cell’s DNA Updated march 2006 Created by C. Ippolito May 2005

Transforming Bacteria foreign DNA joined to a plasmid genetic marker – allows researchers to find bacteria with foreign DNA Updated march 2006 Created by C. Ippolito May 2005

Chapter 13 Section 4 Applications of Genetic Engineering Objectives: Describe the usefulness of some transgenic organisms to humans Summarize the main steps in cloning Updated March 2006 Created by C. Ippolito May 2005

Transgenic Organisms Transgenic Organism organisms that contain genes from another organism Transgenic Bacteria make human insulin make human growth hormone Transgenic Plants make own insecticides immune to weed killing chemicals Transgenic Animals with growth hormone – grow faster chickens resistant to bacterial infections Updated march 2006 Created by C. Ippolito May 2005

Cloning Clone genetically identical cells produced from a single cell genetically identical to parent from whom cell was taken Try it! Updated march 2006 Created by C. Ippolito May 2005