Background

Farmers have been genetically modifying organisms for centuries to encourage specific traits in crops, such as drought resistance or high yield. This has relied on cross breeding between individual plants to obtain the desirable trait in subsequent generations. There is now the option to remove genes, alter them or place genes for selected traits directly into another organism, which is known as genetic modification (GM). These genes do not have to originate from the same plant species or even originate from plants at all.

In Australia, products derived from GM crops for use in processed foods include cotton, safflower and canola while non-food crops include blue carnations. Cottonseed oil is produced from GM cotton, and can be found in edible vegetable oils and margarines. GM cotton, GM safflower and GM canola are the only GM products approved to be grown commercially in Australia, although there are several approved for controlled releases. Some imported GM food crop products can be found in processed foods in Australia. There are also GM components in various medications and stockfeed. In addition, enzymes from GM sources are used in the creation of some foods such as sugar and cheese, although there are no GM ingredients found in the end product. No fresh vegetables, fruit, meat, fish or agricultural products sold in Australia are GM, other than those listed above. Many people object to the use of GM crop plants while others argue that these crops are actually better for the environment.

Prior Knowledge

Knowledge of DNA structure would be beneficial.

Learning Intentions

In this program students will:

• Learn how to extract DNA from foods
• Learn how PCR makes copies of the target DNA
• Discover techniques for setting up, running and staining electrophoresis gels
• Discover which of the food samples have come from a genetically modified plant

Activities

Students will:

• Extract DNA from a variety of foods
• Use PCR to make copies of target DNA
• Set up and run gel electrophoresis
• Analyse results

VCE links

• Amplification of DNA using polymerase chain reaction and the use of gel electrophoresis in sorting DNA fragments.
• The use of recombinant plasmids as vectors.
• The use of genetically modified and transgenic organisms in agriculture to increase crop productivity and to provide resistance to disease.

Learning Continuum

The following Learning Continuum is a guide for teachers to show the links between the programs Ecolinc offers onsite, online and through outreach. The Learning Continuum can be used to access Ecolinc resources to support the development of units of work.

Ecolinc Learn Online is an online learning management system offering interactive online courses for students and teachers. These courses can be undertaken either as a pre-visit, post-visit or stand-alone. Students are encouraged to do the pre-learning course before coming to Ecolinc for the onsite program.