Which of the following best describes electrophoresis?

Electrophoresis is best described as a technique used to separate DNA, RNA, or proteins based on their size and charge. This method relies on the application of an electric field to a gel matrix, where the molecules being separated are loaded. As the electric current passes through the gel, the molecules migrate towards the electrode with the opposite charge. Smaller molecules generally move faster and farther through the gel than larger ones, allowing for separation based on size. Additionally, the charge of the molecules affects their movement; for example, negatively charged DNA will move towards the positive electrode. This technique is widely used in molecular biology for various applications, including analyzing genetic material and protein characterization.

The other choices present different concepts: the method for increasing the yield of genetically modified crops refers to agricultural biotechnology practices, determining the nucleotide sequence of DNA pertains to sequencing techniques, and culturing bacterial cells in a laboratory relates to microbiological methods. While all these concepts are important in biotechnology, they do not accurately describe electrophoresis.