What compounds move through the chromatography column during the separation process?

The correct answer indicates that proteins in solution move through the chromatography column during the separation process. This is because chromatography is a technique designed to separate components of a mixture based on their size, charge, or affinity for the stationary phase of the column. In the context of GFP purification, the mixture typically contains various proteins, and the goal is to isolate GFP from others.

As the protein solution is passed through the chromatography column, different proteins will interact with the resin in distinct ways, which leads to their separation based on specific properties. For instance, proteins can be separated using techniques such as affinity chromatography, where a ligand specific to GFP is attached to the column, allowing GFP to bind while other proteins are washed away.

When considering the context of purification, other compounds such as lipids or DNA fragments do not play a major role in a typical GFP purification process, as they are not the target for separation. While other proteins might also be present in the mixture, the emphasis is on the proteins that interact with the chromatography medium in the column. Thus, the movement of proteins in solution is central to the chromatography technique used in this scenario.