The following figure demonstrates the genotypic adaptive landscape for bacteria growing in media without antibiotics.The height of the bars associated with a genotype indicates the fitness of that genotype.The R allele confers resistance to antibiotics,and the C allele compensates for the loss of fitness that the R allele confers in the absence of antibiotics.The rc haplotype lacks both compensation and resistance.Based on this landscape,why are resistance and compensation unlikely to be lost even in the absence of antibiotics?
A)A lack of mutation will prevent the haplotypes from changing.
B)Epistasis will maintain haplotype frequencies.
C)Haplotype frequencies do not change in Hardy-Weinberg populations.
D)RC populations are stuck on a local maximum.
E)Bacteria evolve slowly.

Question

The following figure demonstrates the genotypic adaptive landscape for bacteria growing in media without antibiotics.The height of the bars associated with a genotype indicates the fitness of that genotype.The R allele confers resistance to antibiotics,and the C allele compensates for the loss of fitness that the R allele confers in the absence of antibiotics.The rc haplotype lacks both compensation and resistance.Based on this landscape,why are resistance and compensation unlikely to be lost even in the absence of antibiotics? 
A)A lack of mutation will prevent the haplotypes from changing. 
B)Epistasis will maintain haplotype frequencies. 
C)Haplotype frequencies do not change in Hardy-Weinberg populations. 
D)RC populations are stuck on a local maximum. 
E)Bacteria evolve slowly.

Quizplus · Accepted Answer

The presence of a local maximum on the landscape for the RC haplotype means that any mutations that occur in this genotype will likely result in a decrease in fitness, making it unlikely for it to switch to a different genotype. Therefore, both resistance and compensation are likely to be maintained even in the absence of antibiotics.

The Following Figure Demonstrates the Genotypic Adaptive Landscape for Bacteria