Final answer:
The chain termination method of sequencing uses fluorescently labeled dideoxynucleotides to generate DNA fragments that terminate at different points. These fragments are separated by gel electrophoresis, and the sequence can be determined by reading the gel and identifying the color of each band.
Step-by-step explanation:
The chain termination method of sequencing is a DNA sequencing technique that involves the use of fluorescently labeled dideoxynucleotides (ddNTPs). These ddNTPs are similar to regular deoxynucleotides (dNTPs), except they lack a hydroxyl group at the site where another nucleotide would normally attach to form a chain. When a ddNTP is incorporated into the growing DNA strand during replication, it terminates the replication process. By using a mixture of regular dNTPs and fluorescently labeled ddNTPs, the sequencing process generates multiple short DNA fragments that terminate at different points. These fragments are then separated by gel electrophoresis, creating a ladder-like pattern that reflects the size of the DNA strands and the ddNTPs incorporated at each position. The sequence of the template DNA strand can be determined by reading the gel and identifying the color of each band on the ladder.