Question

The researcher inoculates the test population of bacteria onto glucose salts agar containing penicillin and also on nutrient agar containing penicillin. She counts 25 colonies on the glucose salts plate lacking histamine and 32 colonies on the nutrient agar. Which of the following statements is TRUE? a. The colonies on both plates contain penicillin-resistant mutants. b. The glucose salts plate contains some mutants. c. The bacteria on the glucose salts medium are mutants while the bacteria on the nutrient agar are wild type. d. The bacteria growing on the nutrient agar are mutants while those growing on the glucose salts medium are wild type. e. The bacteria that failed to grow on the glucose salts medium are double mutants.

Answer 1

Answer: Option A

Explanation:

An experiment was performed in which a bacterial population was inoculated in the glucose-salt agar penicillin and another on the nutrient agar containing penicillin.

Both of the plates that contains bacteria have penicillin mutant bacteria. This is so because both the plates contains penicillin, there was growth seen on both the plates.

On one plate the bacteria have grown with no histidine( his mutant) and on another using the nutrient agar.

So, the colonies on the both the medium is penicillin-resistant mutant.