Multiple Choice
The DNA molecule is usually found in which structural form in cells?
4
views
7. DNA and Chromosome Structure
DNA Structure
Struggling with Genetics?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
In gel electrophoresis, what is the relationship between the size of a DNA fragment and the distance it migrates through the gel?
A
All DNA fragments migrate the same distance regardless of size.
B
Smaller DNA fragments migrate farther than larger fragments.
C
DNA fragment size does not affect migration distance in the gel.
D
Larger DNA fragments migrate farther than smaller fragments.
Verified step by step guidance1
Understand that gel electrophoresis separates DNA fragments based on their size because the gel acts like a molecular sieve.
Recall that DNA molecules are negatively charged and move towards the positive electrode during electrophoresis.
Recognize that smaller DNA fragments can navigate through the pores of the gel matrix more easily and therefore migrate farther than larger fragments.
Larger DNA fragments experience more resistance and move more slowly, resulting in shorter migration distances.
Conclude that there is an inverse relationship between DNA fragment size and migration distance: as fragment size decreases, migration distance increases.
Related Videos
Related Practice
