A mixture of fragmented DNA was electrophoresed in an agarose gel. After staining the gel with ethidium bromide, no DNA bands were observed. What could be the reason?
A mixture of fragmented DNA was electrophoresed in an agarose gel. After staining the gel with ethidium bromide, no DNA bands were observed. What could be the reason?
The reasons are as follows:
(i) DNA sample that was loaded on the gel may have got contaminated with nuclease (exo-or endo-or both) and completely degraded.
(ii) Electrodes were put in opposite orientation in the gel assembly that is anode towards the wells (where DNA sample is loaded). Since DNA molecules are-negatively charged, they move towards anode and hence move out of the gel instead of moving into the matrix of gel.
(iii) Ethidium bromide was not added at all or was not added in sufficient concentration and so DNA was not visible.
-
Illustrate the design of a bioreactor. Highlight the difference between a flask in your laboratory and a bioreactor which allows cells to grow in a continuous culture system.
3 years ago
-
Describe the role of Agrobacterium tumefacient in transforming a plant cell.
3 years ago
-
For selection of recombinants, insertional inactivation of antibiotic marker has been superseded by insertional inactivation of a marker gene coding for a chromogenic substrate. Give reasons.
3 years ago
-
Name the regions marked A, B and C.
3 years ago
-
Identify and explain steps ‘A’, ‘B’ and ‘C’ in the PCR diagram given below.
3 years ago
Currently viewing this topic 1 guest.
- 321 Forums
- 27.3 K Topics
- 53.8 K Posts
- 26 Online
- 12.4 K Members