Question

Predictions: Indicate your predictions for growth of E.coli or no growth of E.coli based on the presence (+) or absence (-) of the plasmid and the growth medium. Explain your reasoning for each prediction. Lysogeny broth (LB) is a nutritionally rich medium primarily used for the growth of bacteria.

+ plasmid on LB plate

- plasmid on LB plate

+ plasmid on LB plate treated with ampicillin

- plasmid on LB plate treated with ampicillin

+ plasmid on LB plate treated with ampicillin and X-gal

- plasmid on LB plate treated with ampicillin and X-gal

Answer 1

Media Conditions	Ecoli :Growth/No growth	Explaination
+ plasmid on LB plate	growth	E coli grow on LB media in presence or absence of plasmid because LB media is nutrient rich media for bacterial growth.
-plasmid on	growth
+plasmid on LB plates treated with ampicillin	growth	Ecoli containing plasmid grow on ampicillin suplemented LB media because plasmid provide antibiotic resistance (ampicillin resistance) to E coli so it grow well in presence of amp supplemented media.
- plasmid on LB plates treated with ampicillin	no growth	E coli which do not contain plasmid do not grow in presence of ampicillin supplemented media because E coli is sensitive to amp antibiotic.
+ plasmid on LB plate treated with ampicillin and X gal	Blue colonies growth	E coli colonies grow well because of presence of plasmid they are resistant to ampicillin and colonies are blue in colour because beta galactosidase on addition of X gal give a coloured reaction ie, blue colour. Here no gene of interest inserted inside plasmid so no insertional inactivation of beta galactosidase so it is capable of production of blue colour colonies in presence of X gal.
- plasmid on LB plate with ampicillin and X gal	No growth	No bacterial growth because E. coli does not contain plasmid so E coli is sensitive to ampicillin and no bacterial growth