Final answer:
Amplified DNA fragments are separated in DNA fingerprinting by gel electrophoresis, where fragments are sorted by size and visualized based on their unique patterns.
Step-by-step explanation:
In the process of DNA fingerprinting, amplified fragments of DNA are separated from one another using gel electrophoresis. This technique involves the use of a gel usually made from agarose, through which an electric current is applied. DNA fragments, which are negatively charged, move towards the positive electrode. The smaller the DNA fragment, the faster and further it moves through the gel. As a result, the fragments are separated by size, with larger fragments being closer to the top of the gel and smaller fragments nearer to the bottom. After the electrophoresis, the DNA bands are stained to visualize the unique DNA patterns that are used in forensics, paternity tests, and criminal investigations.