A DNA molecule is cut with two different restriction enzymes known to cleave it only once each. After gel electrophoresis, three different DNA fragments are detected. This result means that the original DNA molecule was:
A)circular.
B)linear.
C)It is not possible to make this determination from the information provided.

Question

Quizplus · Accepted Answer

The presence of three different DNA fragments after cleavage with two different restriction enzymes that cut the original DNA only once each suggests that the original DNA molecule was linear, as circular DNA would result in only two fragments.

A DNA Molecule Is Cut with Two Different Restriction Enzymes