A geneticist uses a plasmid for cloning that has the lacZ gene and a gene that c

Question

A geneticist uses a plasmid for cloning that has the lacZ gene and a gene that confers resistance to penicillin. The geneticist inserts a piece of foreign DNA into a restriction site that is located within the lacZ gene and uses the plasmid to transform bacteria. Explain how the geneticist can identify bacteria that contain a copy of a plasmid with the foreign DNA.

Bacteria with the correct plasmid will produce the only living colonies on selective media containing penicillin and X-gal.

Bacteria with the correct plasmid will produce white colonies on selective media containing penicillin and X-gal.

Bacteria with the correct plasmid will produce blue colonies on selective media containing penicillin and X-gal.

Bacteria with a plasmid containing foreign DNA cannot be identified until the bacterial cells are lysed and the DNA extracted and analyzed.

Bacteria with the correct plasmid will produce both blue and white colonies on selective media containing penicillin and X-gal.

Explanation / Answer

Answer: Bacteria with the correct plasmid will produce white colonies on selective media containing penicillin and X-gal.

Bacteria that have intact lac Z geneproduce functional B galactosidase and cleave the X gal to produce blue colonies.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.