Gel electrophoresis is a technique used by molecular biologists to analyze samples of DNA or proteins. DNA was collected from the scene of a crime. Gel electrophoresis was used to compare the crime scene DNA to the victim’s DNA along with the two suspects of the crime.

Question

Figure 1 shows the gel sheet after each sample was run. Table 1 shows the distance each band traveled from the origin. The samples were run in the same gel with a DNA standard marker for comparison. Table 2 shows the results of the standard.

Figure 1. Created for Albert. All rights reserved.
Table 1
Standard (
mm
) Crime Scene (
mm
) Suspect 1 (
mm
) Suspect 2 (
mm
) Victim (
mm
)
18
29
26
29
8
23
33
29
33
18
28
34
30
34
25
34
35
32
35
30
45
47
36
47
32
47
48
48
34
Table 2
Distance (
mm
) Size of Fragment in Base Pairs (
bp
)
18
23109
23
9416
28
6557
34
4361
45
2328
47
2027
Which of the following hypotheses is supported by the data gained from the gel electrophoresis in Figure 1 and Table 1?

Select one answer
A
Suspect 1 was at the crime scene because his or her DNA markers matched those of the DNA at the crime scene.
B
Suspect 2 was at the crime scene because his or her DNA markers matched those of the DNA at the crime scene.
C
Both Suspect 1 and Suspect 2 were at the crime scene because their DNA markers matched those of the victim's.
D
Neither Suspect 1 or Suspect 2 were at the crime scene because neither of their DNA matches the DNA standard used in the electrophoresis.

Answer 1

A
Suspect 1 was at the crime scene because his or her DNA markers matched those of the DNA at the crime scene.