Gene sequencing. Gloved hand manipulates an agarose gel plate during electrophoresis. This is done to study the sequence of bases on a sample of DNA (deoxyribonucleic acid), represented by the fluorescent bands seen here. The sequence of bases along the length of a DNA molecule determines the characteristics of the organism from which it was taken. DNA is fragmented by enzymes, placed in the gel seen here and separated by electrophoresis, the application of an electric field. This DNA sample is from a tomato plant. Research into the DNA of crops may allow the development of hardier plants, and the introduction of desirable traits, such as an increased ripeness period.