PATHOLOGY

PATHOLOGY MCQ

GENETICS AND DISEASE

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
In gel electrophoresis, which DNA Fragments move farthest from the starting point?
A
Large Fragments
B
Small Fragments
C
Medium Fragments
D
Smooth Fragments
Explanation: 

Detailed explanation-1: -Because all DNA fragments have the same amount of charge per mass, small fragments move through the gel faster than large ones.

Detailed explanation-2: -Because DNA is negatively-charged, it moves toward the positive electrode. The DNA fragments that are shortest will travel farthest, while the longest fragments will remain closest to the origin.

Detailed explanation-3: -Smaller molecules migrate through the gel more quickly and therefore travel further than larger fragments that migrate more slowly and therefore will travel a shorter distance.

Detailed explanation-4: -The smallest fragments travel the most distance. DNA is a negatively charged molecule and it will migrate to the positively charged electrode when an electric current is supplied to the gel. The shorter strands of DNA move faster across the gel than longer strands, the fragments are organized in size order.

Detailed explanation-5: -Gel electrophoresis is used to segregate DNA fragments according to mass and size. DNA is negatively charged and it will travel towards the positive electrode. Hence separation will be on the size of the fragments. The smaller DNA molecules move faster and farthest followed by the larger ones.

There is 1 question to complete.