5.12-5.16 biology : genetic modification

what is DNA

double stranded helix molecule that carries genetic information. Made of many nucleotides with bonds between complementary bases

gene

a section of DNA that codes for a specific protein

genetic engineering

technique used to transfer genes from the cells of a donor organism to those of a recipient organism

transgenic

an organism that has been engineered with a gene from another different species

restriction enzyme

used to cut the gene of interest and the vector to form sticky ends (cut DNA at specific sites)

ligase

enzyme which is used to join the complimentary sticky ends of the gene of interest and vector

vector

a structure which can be used to transfer genes in genetic engineering. can be plasmids, viruses, liposomes

what are plasmids

extrachromosomal circular pieces of DNA found in bacteria.

recombinant def

contains DNA from two or more different sources/organisms

how does GM improve food production

• greater resistance to pests and herbicides

• increase in nutritional content

• drought resistance and salty soil toleration

• more efficient photosynthesis so greater yield

• longer shelf life

how can GM crops affect environment and food chains

• genes could find way into genomes of other non crop plants which could cause resistance in pests and weeds

• if more herbicides are used, then the weeds will die so organisms that feed on them have less food

• biodiversity could improve as less pesticide used so fewer organisms die so more food chains exist