Tornadoes only form under certain weather conditions. There are three types of airs for a tornado to form, warm humid air close to the ground, cold air in the upper atmosphere, and hot dry air on top that form a cap.(na, 2010) Hurricanes can form tornadoes adding to their destructive power.
Genetically modified crops. Genetically modified crops (GM crops, or biotech crops) are plants used in agriculture, the DNA of which has been modified using genetic engineering techniques. In most cases the aim is to introduce a new trait to the plant which does not occur naturally in the species.
The resulting plant is said to be âgenetically modifiedâ although in reality all crops have been âgenetically modifiedâ from their original wild state by domestication, selection, and controlled breeding over long periods of time. GM or transgenic crop is a plant that has a novel combination of genetic material obtained through the use of modern biotechnology. For example, a GM crop can contain a gene(s) that has been artificially inserted instead of the plant acquiring it through pollination.