Question

Suppose one restriction enzyme (enzyme A) makes two cuts in a linear DNA fragment and another restriction enzyme (enzyme B) makes one cut in that same DNA. The cuts are not in the same place, and none of the cut fragments are exactly the same size. The restriction digest is set up on an electrophoresis gel. How many bands should the gel pick up if only enzyme A is used in the restriction digest?

Answer 1

When only enzyme A is used in the restriction digest, it will produce three distinct bands on the gel.

Step-by-step explanation:

When only enzyme A is used in the restriction digest, it will make two cuts in the linear DNA fragment. Since the cuts are not in the same place, it will produce three fragments of different sizes.

Each cut site in the DNA fragment will create two ends, resulting in a total of four ends. These ends will migrate at different speeds through the gel during electrophoresis, producing three distinct bands on the gel.