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4. During gel electrophoresis:
a) DNA is "cut" into smaller pieces using restriction enzymes.
b) The "cut" DNA is placed into small depressions at one end of a sheet of gel in an electrophoresis chamber.
c) An electrical field is applied to the gel by attaching electrodes to both ends.
d) The "cut" pieces of DNA begin to move toward one electrode or another. Small DNA fragments or those that are highly charged move faster than those DNA fragments that are larger or less highly charged.
e) The DNA fragments eventually separate.
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