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Section 13-1: Changing the Living World
Humans use selective breeding to pass desired traits on to the next generation of organisms.
Breeders can increase the genetic variation in a population by inducing mutations, which are the ultimate source of genetic variability.
Section 13-2: Manipulating DNA
Scientists use their knowledge of the structure of DNA 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.
Knowing the sequence of an organism's DNA allows researchers to study specific genes, to compare them with the genes of other organisms, and to try to discover the functions of different genes and gene combinations.
Section 13-3: Cell Transformation
During transformation, a cell takes in DNA from outside the cell. This external DNA becomes a part of the cell's DNA.
If transformation is successful, the recombinant DNA is integrated into one of the chromosomes of the cell.
Section 13-4: Applications of Genetic Engineering
Using the basic techniques of genetic engineering, a gene from one organism can be inserted into cells from another organism. These transformed cells can then be used to grow new organisms.