Final answer:
Cutting a linear piece of DNA two times produces three fragments. This is a standard calculation in molecular biology, where cutting by specific enzymes creates fragments that can be visualized by gel electrophoresis using a DNA ladder.
Step-by-step explanation:
When you cut a linear piece of DNA two times, you will end up with three DNA fragments. This is because each cut breaks the DNA into two parts, and after two cuts, there will be an additional fragment. For example, if you have a linear DNA like this: |--A--|--B--|--C--| and you make cuts between A-B and B-C, you will end up with three fragments: A, B, and C.
In the context of genetic experiments, various enzymes like EcoRI and HindIII may be used to create cuts at specific sites. These enzymes often produce sticky ends, which are overhanging sequences of unpaired nucleotides that can be recombined with complementary DNA fragments. Also, in a molecular biology technique such as gel electrophoresis, a DNA ladder with known fragment sizes is employed to gauge the sizes of the DNA pieces run through a gel, which helps visualize and analyze the resulting fragments.