Over the past 20 years, scientists have been using technology on nature to improve food supplies. They are producing genetically modified (GM) food by modifying, or changing, the genes of plants and animals. Genes are the codes in the cells of every living thing that determine the way they look and grow In humans, genes determine characterstics such as the color of our eyes and how tall weaer. By changing the genes of plants, scientists can cause crops to produce more, become resistant to peys and disease, and have more nutritional value. Genetically modifined plants can have great benefits by increasing food supplines, protecting the environment, and even improving nutrition.