The student plots fragment size (log scale) vs. migration distance (mm from well) for the 100-bp ladder.
Why does the relationship between log(size) and migration distance produce a near-straight line?
- A
Migration distance is independent of fragment size
- B
DNA fragments do not separate by size
- Ccheck_circle
Smaller fragments migrate exponentially faster through the gel matrix
- D
Voltage causes random movement
Explanation
In agarose gels, smaller DNA fragments migrate faster through pores. Mobility scales roughly with -log(size) over a working range, producing a linear log(size) vs. distance plot used for size estimation.