Question

3 bacterial growth result 2 resistant and nonresistant e. coli bacteria samples were spread on the agar plates below and incubated for 24 hours. select the true statements from the list below. check all that apply the resistant e. coli strain grows on streptomycin negative plates. the nonresistant e. coli strain grows on streptomycin negative plates. the nonresistant e. coli strain grows the same on streptomycin positive or negative plates.

Explanation:

1. Resistant bacteria can grow in the presence of the antibiotic they are resistant to, and also on plates without the antibiotic. So, resistant E. coli will grow on streptomycin - negative plates.
2. Non - resistant bacteria will grow on plates without the antibiotic (streptomycin - negative plates) as there is no inhibitory substance for them in this environment.
3. Non - resistant E. coli will be inhibited by streptomycin on streptomycin - positive plates and will not grow the same as on streptomycin - negative plates.

Answer:

The resistant E. coli strain grows on streptomycin negative plates.
The nonresistant E. coli strain grows on streptomycin negative plates.