CHANGING THE LIVING WORLD OBJECTIVES: 13.1 Explain the purpose of selective breeding. Describe two techniques used in selective breeding. Tell why breeders try to induce mutations.

________ breeding allows only those animals with desired ______ to produce offspring. We use selective breeding, which takes advantage of naturally occurring _______ variations in plants, animals, and other organism, to pass desired traits on to the next generation.

____________ is the crossing of dissimilar individual to bring together the best of both organisms (______). _____________ is the continued breeding of individuals with similar characteristics. There is always a chance that a ______ between two individuals will bring together two ______ alleles for a genetic defect. Examples of defects: _______, ______________ in German shepherds and golden retrievers.

Breeders can increase variation in a population by inducing _________, which are the ultimate source of genetic __________. Mutations are an _________ changes in DNA. Using these techniques scientists have made new ________ and ________.

MANIPULATING DNA OBJECTIVE: 13.2 Explain how scientists manipulate DNA.

Scientists use their knowledge of the structure of ____ and its chemical properties to study and change DNA molecules. Different techniques are used to extract DNA from cells, to cut DNA into smaller pieces, to identify the sequence of bases in a DNA molecule, and to make unlimited copies of DNA. _________ __________ makes changes in the DNA code of a living organisms.

__________ enzymes cuts DNA at specific sequence of ___________. ____ ___________ is the method of separating DNA fragments. DNA fragments are placed into one end of a porous gel, and an electric _________ is applied to the gel. ___________ charged DNA fragments move toward the positive end of the gel.

The smaller the DNA fragments, the ______ and ________ they move. Gel electrophoresis can be used to compare _________. It can locate and id a particular gene. ___________ DNA is when a gene from one organism is splice and attached to another organisms DNA.

__________ _______ ________ (PCR) makes copies of a particular gene. A ______ is added (a place for DNA polymerase to start working) and the DNA is heated into two separate strand. DNA polymerase makes copies of the region between primers.

heat

CELL TRANSFORMATION OBJECTIVES: 13.3 Summarize what happens during transformation. Explain how you can tell if a transformation experiment has been successful.

During ____________, a cell takes in DNA from outside the cell. This ________ DNA becomes a __________ of the cell’s DNA. _______ are circular DNA molecules. 1.The plasmid has to have a sequence that promote ________. 2. It has to have a genetic marker.

A ________ marker is a gene that makes it possible to distinguish bacteria that carry the plasmid (and the foreign DNA) from those that don’t. These markers allows us to distinguish that plasmid from other cells that does not have the __________ DNA. After transformation the cells are treated with and ___________. Only those cells that have been transformed ______, because only they carry a ________ gene.

Many plant cells can be transformed by using a process that takes advantage of a bacterium. The bacterium in nature inserts a small DNA plasmid that produces ______ in a plant’s cell. They have found they can inactivate the tumor- producing gene and insert a piece of foreign DNA into the plasmid. The recombinant plasmid can then be used to _______ plant cells. DNA can be taken up directly or ________ into a cell.

If _________ is successful, the _____________ DNA is integrated into one of the chromosomes. ___ cells, of animals, are large enough to that DNA can be injected into the nucleus. Once inside _______ normally responsible for DNA repair and recombination may help insert the foreign DNA. The DNA used for recombination also has a genetic marker.

APPLICATIONS OF GENETIC ENGINEERING OBJECTIVES: 13.4 Describe the usefulness of some transgenic organism to humans. Summarize the main steps in cloning.

The ______ nature of genetic mechanism makes it possible to construct organisms that are _________, meaning that contain genes from other species. Transgenic organism – makes _____, ______ hormone, ________ factors. Transgenic animals – improve food supply. Transgenic plants – in % of the soybeans, and 25% of the corn in the U.S., produces natural insecticides, resists weed killer.

A ______ is a member of a population of genetically identical cells produced from a ______ cell. Dolly The cloning of humans, while possible, raises serious ______and _____ issues that caused people to oppose such work