GM plants and food production Flashcards
5.15
what are GM plants?
plants that have had foreign DNA inserted into their genome
what crop plants have been GM?
wheat and maize- to contain a gene from a bacterium that produces a poison to kill insects- making them resistant to insect pests such as caterpillars- this can improve crop yields
why have crop plants also been modified?
to make them resistant to certain herbicides- when the herbicide is sprayed on the crop, it only kills weeds and does not affect the crop plant
why else have crop plants been modified?
to produce additional nutrionitional value and additional vitamins
what does golden rice contain?
genes from another plant and a bacterium which makes the rice grains produce a chemical that is turned into vitamin A in the body- could help to prevent deficiency diseases
why else have some plants been modified?
to be drought-resistant- to grow better in drier conditions
what are the 2 main stages of genetically modifying crops?
introducing the new gene or genes into plant cells
producing whole plants from just a few cells (tissue culture)
what bacterium is used to GM crops?
agrobacterium tumefaciens- regularly inserts plasmids into plant cells, adding genes to the plant chromosomes
what are the advantages of GM crops?
reduced use of pesticides/herbicides so less pollution and better for the environment- cheaper/less time cost for farmers
increased yields from the crops as they are not competing with weeds for resources or suffering from pest damage
more precise method than selective breeding
disease resistant/pest resistant/herbicide resistant
disadvantages of GM crops?
increased cost of seeds- companies that make GM seeds charge more for them to cover the cost of developing them- smaller, poorer farmers cannot compete with larger farms
not accepted by public
long term effects unkown
reduces variation
may affect food chain/environment- reduced biodiversity
