Question

question 4 of 10
the results of gel electrophoresis are shown below. what can you determine about the dna from looking at the results of this test?
a. strand 2 is smaller than strand 3.
b. strand 1 is larger than strand 4.
c. strand 4 is the smallest.
d. strand 2 is larger than strand 4

Explanation:

In gel electrophoresis, smaller DNA fragments move faster and farther towards the positive electrode. Strand 2 is closer to the positive electrode than strand 3, so strand 2 is smaller. Strand 1 is the smallest (closest to + electrode), not strand 4 (so C is wrong). Strand 1 is smaller than strand 4 (so B is wrong). Strand 2 is smaller than strand 4 (so D is wrong).

Answer:

A. Strand 2 is smaller than strand 3.