QUESTION 1 OF 8
What is the primary purpose of adding dye to DNA samples in gel electrophoresis?
To make the DNA molecules move faster through the gel
To allow visualization of DNA bands under UV light
To change the charge of the DNA molecules
To prevent DNA degradation during electrophoresis
QUESTION 2 OF 8
Which statement best describes how DNA fragments are separated in gel electrophoresis?
By their electrical charge only
By their color after staining
By their size as they move through the gel matrix
By their temperature sensitivity
QUESTION 3 OF 8
What property of DNA causes it to move toward the positive electrode during electrophoresis?
Its positive charge
Its negative charge
Its neutral charge
Its molecular weight
QUESTION 4 OF 8
How does the agarose gel matrix affect DNA movement during electrophoresis?
It provides nutrients for DNA stability
It acts as a molecular sieve to separate fragments
It neutralizes the charge of DNA molecules
It increases the speed of all fragments equally
QUESTION 5 OF 8
Which DNA fragments will migrate fastest through an agarose gel?
Larger fragments with more base pairs
Fragments with the strongest negative charge
Smaller fragments with fewer base pairs
Fragments with the most dye molecules attached
QUESTION 6 OF 8
What determines the direction of DNA migration in gel electrophoresis?
The concentration of agarose in the gel
The electrical field between the electrodes
The temperature of the buffer solution
The amount of DNA loaded in each well
QUESTION 7 OF 8
What is the primary purpose of including a DNA ladder in gel electrophoresis?
To calibrate the electrical current
