A eukaryotic gene has "sticky ends" produced by the restriction endonuclease EcoRI.The gene is added to a mixture containing EcoRI and a bacterial plasmid that carries two genes conferring resistance to the antibiotics ampicillin and tetracycline.The plasmid has one recognition site for EcoRI located in the tetracycline resistance gene.This mixture is incubated for several hours,exposed to DNA ligase,and then added to bacteria growing in nutrient broth.The bacteria are allowed to grow overnight and are streaked on a plate using a technique that produces isolated colonies that are clones of the original.Samples of these colonies are then grown in four different media: nutrient broth plus ampicillin,nutrient broth plus tetracycline,nutrient broth plus ampicillin and tetracycline,and nutrient broth without antibiotics.
Bacteria containing a plasmid into which the eukaryotic gene has been inserted would grow in which of the following conditions?
A)in the nutrient broth only
B)in the nutrient broth and the tetracycline broth only
C)in the nutrient broth,the ampicillin broth,and the tetracycline broth
D)in the ampicillin broth and the nutrient broth

Question

Quizplus · Accepted Answer

Bacteria with the plasmid containing the eukaryotic gene inserted into the tetracycline resistance gene would lose tetracycline resistance but retain ampicillin resistance, allowing them to grow in ampicillin-containing and antibiotic-free media.

A Eukaryotic Gene Has "Sticky Ends" Produced by the Restriction