Question

You are working in a molecular biology lab and, unknown to you, your lab partner left

the foreign genomic DNA that you are planning to clone on the lab bench overnight

instead of storing it in the freezer. As a result, it was degraded by nucleases, but still

used in the experiment. The plasmid, on the other hand, is fine. What results would

you expect from your molecular cloning experiment?

1. There will be no colonies on the bacterial plate.

2. There will be blue colonies only.

3. There will be blue and white colonies.

4. The will be white colonies only.

Answer 1

2. There will be blue colonies only. 

As blue colonies have plasmids without insert whereas white colonies have plasmids with the foreign insert.