1. Station 1
Gel Electrophoresis

2. Gel Electrophoresis overview
Gel electrophoresis is a process that can be used to determine how genetically similar organisms are to one another.
This is done by observing the pattern of DNA fragments (or bands on the gel)
Similar band patterns= more similar genetically

3. Let’s Practice:
Looking at the diagram to the left, which two organisms are the most genetically similar?

4. Let’s Practice: You should have chosen Species A and Species B.
What is my rationale?
Observing the bands, I can
see that Species A and B have a similar band pattern.
Specifically, these two species
match up perfectly on three of
their DNA fragments, while
Species C only matches up
with one of the bands.

5. Now it is your turn!
Directions: Observe the patterns of DNA fragments to determine common ancestry between organisms
Remember the common ancestor will have a similar pattern with ALL of the other organisms presented on the gel.

6. Gel # 1
Which two organisms are most related according to the pattern of DNA fragments?

7. Gel # 2
Which organism is a possible common ancestor of the other three organisms present?

8. Gel # 3
Which organism is a possible common ancestor of the other three organisms present?