Question

Electrophoresis separates DNA fragments of different sizes with ____ fragments moving faster to the ____ pole.

1. Shorter, negative
2. Labeled, Southern
3. Longer, negative
4. Longer, positive
5. Shorter, positive

Answer 1

Ans.

Using Gel electrophoresis charged molecules like DNA,RNA and proteins can be separated according to their size.Using this technique we can distinguish DNA fragments of different length.The basic principle of electrophoresis is that, DNA being a charged molecule will move across the gel if an electric current is passed across it.DNA being negatively charged, when an electric current is passed through the gel,it will move towards the positively charged end.Since DNA strands that are shorter is size moves quickly through the gel, the fragments gets arranged in order of their size.Once separated and arranged, by using appropriate dyes,radioactive labels or fluorescent tags,the DNA can be seen as bands that appear on the gel.

Thus, the answer is 'Shorter, positive'. Hence,the statement 'Electrophoresis separates DNA fragments of different sizes with Shorter fragments moving faster to the positive pole.