Question

Two strains of E. coli, A and B, are inoculated into a chemostat in equal proportions. After one generation the frequency of strain B is 20%. What is the fitness of strain B relative to strain A?

A. 0
B. 0.2
C. 0.25
D. 0.75
E. 1

Answer 1

The fitness of strain B relative to strain A is 0.2.

Step-by-step explanation:

The fitness of strain B relative to strain A can be calculated by comparing their frequencies after one generation. In this case, if the frequency of strain B is 20% after one generation, it means that 20% of the population is made up of strain B. Since the initial proportions of strains A and B were equal, strain B has increased its frequency by 20% relative to strain A. Therefore, the fitness of strain B relative to strain A is 0.2.