Answer: Its measured with the use of gel electrophoresis.
Explanation: Scientists use a method known as gel electrophoresis to measure the lengths of DNA fragments. Electrophoresis works because fragments carry a small charge.
gel electrophoresis. This method relies on the fact that DNA fragments are charged, and it is an alternative to more expensive methods, such as X-ray crystallography, which was responsible for the discovery of the double-helix structure of DNA.
to determine the sizes of these unknown fragments, scientists usually plot a graph. On the x-axis is the distance traveled by each band in the ladder in millimeters, while on the y-axis is the size of each band. When the points are connected by a curve, the size of any band can be extrapolated from the curve after measuring the distance traveled by that band in millimeters.
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