A halophilic, aerobic mesophile has a generation time of 20 minutes. You place 1 × 10⁴ of these organisms on an appropriate solid medium, and incubate the plate for 100 minutes. Select the False statement.
A) The growth medium contains NaCl.
B) The organism will grow at 40ᵒC.
C) After incubation, a colony on the plate contains 3.2 × 10⁵ cells.
D) After incubation, a colony on the plate contains 5 × 10⁴ cells.
E) The organism produces superoxide dismutase and catalase.

Question

A halophilic, aerobic mesophile has a generation time of 20 minutes. You place 1 × 10⁴ of these organisms on an appropriate solid medium, and incubate the plate for 100 minutes. Select the False statement.
A) The growth medium contains NaCl.
B) The organism will grow at 40ᵒC. 
C) After incubation, a colony on the plate contains 3.2 × 10⁵ cells.
D) After incubation, a colony on the plate contains 5 × 10⁴ cells.
E) The organism produces superoxide dismutase and catalase.

Quizplus · Accepted Answer

According to the given generation time of the organism, the number of cells after 100 minutes can be calculated using the equation Nf = Ni x 2^(t/g), where Nf is the final number of cells, Ni is the initial number of cells, t is the incubation time, and g is the generation time. Plugging in the values, we get Nf = 1 × 10⁴ x 2^(100/20) = 3.2 × 10⁵ cells. Therefore, statement C is true and statement D is false. Statements A, B, and E are not contradicted by the information given.

A Halophilic, Aerobic Mesophile Has a Generation Time of 20 Minutes