Genetic engineering is a process in which the genome of an organism is modified to introduce a desirable characteristic. The genome is all the genetic material of the organism. Usually a gene from one organism is cut out and put into the cells of another organism.
The organism that receives the new gene is called a genetically modified (GM) organism. Because it now carries the extra gene, it can make a protein that it could not make before, and this gives it the new characteristic.
In agriculture, examples include crops that make their own insecticide so that fewer pests survive, crops that tolerate herbicides, and crops with extra vitamins, such as rice that contains a nutrient the body turns into vitamin A. Unlike selective breeding, genetic engineering can add a useful gene from a different species and it can change the organism within a single generation.
