Passage I

A scientist discovered that cells of a new strain of bacteria, Bacteria X, form colonies when incubated for 72 hr at 37°C on a growth medium having a pH of 7 and an NaCl concentration of 5 g/L. To determine whether these conditions are optimal for the growth of Bacteria X, the scientist conducted an experiment in which incubation temperature, and the pH and the NaCl concentration of the growth medium, were varied. In each trial, Bacteria X cells were incubated for 72 hr, and colony growth was then assayed by determining the average colony diameter (ACD) of the colonics that grew during the incubation (see the table).

4. The scientist predicted that the ACD for Bacteria X colonies would be greatest when the bacteria were incubated at a temperature of 37℃ on a growth medium having a pH of 7 and an NaCl concentration of 5 g/L. Are the results in the table consistent with this prediction?

Answer and Explanation

Your Answer is

Correct Answer is J

Explanation

It can be seen from the table that under the same other conditions, when the NaCl concentration is 10 g/L, the ACD is higher, so the statement in the question stem is wrong