Biotechnology

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These and other STR data exonerated Washington and led Tinsley to plead guilty to the murder.

(a)

Semen on victim

Earl Washington

Source of sample

Kenneth Tinsley

STR marker 1

STR marker 2

STR marker 3

(b)

17, 19

16, 18

17, 19

13, 16

12, 12

14, 15

11, 12

13, 16

12, 12

Slide 103

Environmental Cleanup

Genetic engineering can be used to modify the metabolism of microorganisms

Some modified microorganisms can be used to extract minerals from the environment or degrade potentially toxic waste materials

Biofuels make use of crops such as corn, soybeans, and cassava to replace fossil fuels

Slide 104

Agricultural Applications

DNA technology is being used to improve agricultural productivity and food quality

Slide 105

Animal Husbandry

Genetic engineering of transgenic animals speeds up the selective breeding process

Beneficial genes can be transferred between varieties or species

Slide 106

Genetic Engineering in Plants

Agricultural scientists have endowed a number of crop plants with genes for desirable traits

The Ti plasmid is the most commonly used vector for introducing new genes into plant cells

Genetic engineering in plants has been used to transfer many useful genes including those for herbicide resistance, increased resistance to pests, increased resistance to salinity, and improved nutritional value of crops

Slide 107

Fig. 20-25

Site where restriction enzyme cuts

T DNA

Plant with new trait

Ti plasmid

Agrobacterium tumefaciens

DNA with the gene of interest

Recombinant Ti plasmid

TECHNIQUE

RESULTS

Slide 108

Safety and Ethical Questions Raised by DNA Technology

Potential benefits of genetic engineering must be weighed against potential hazards of creating harmful products or procedures

Guidelines are in place in the United States and other countries to ensure safe practices for recombinant DNA technology

Slide 109

Most public concern about possible hazards centers on genetically modified (GM) organisms used as food

Some are concerned about the creation of “super weeds” from the transfer of genes from GM crops to their wild relatives

Slide 110