What does gel electrophoresis primarily accomplish?

Gel electrophoresis is a laboratory technique primarily used to separate nucleic acids (DNA and RNA) or proteins based on their size and charge. During this process, an electric current is applied to a gel matrix, which allows molecules to move through the gel. Smaller molecules can navigate through the gel more easily than larger ones, leading to their separation.

This technique is crucial in various fields, including molecular biology, genetics, and biochemistry, for analyzing samples, purifying specific molecules, and preparing them for further study or use. By separating these macromolecules, scientists can assess the quantity and size of the DNA or proteins, which is essential for applications such as genotyping, sequencing, and protein analysis.

The other options represent different types of laboratory techniques or measurements that do not involve separation through gel electrophoresis. For instance, amplification of DNA is typically accomplished using techniques such as PCR (Polymerase Chain Reaction), visualization of cellular structures usually involves microscopy methods, and measuring pH levels is performed using pH meters or indicators, which are unrelated to electrophoresis. Thus, the primary function of gel electrophoresis is indeed the separation of DNA, RNA, or proteins.