Question

If the bacterium Staphylococcus aureus experiences a cost for maintaining one or more antibiotic-resistance genes, what would happen in environments that lack antibiotics?

a)The number of genes conveying antibiotic resistance would increase in these bacteria

b)These genes would be maintained in case the antibiotics appear.

c)These bacteria would be outcompeted and replaced by bacteria that have lost these genes.

Answer 1

c)These bacteria would be outcompeted and replaced by bacteria that have lost these genes.

Step-by-step explanation:

The genetic traits that make the organisms better adapted to the prevailing conditions are favored by natural selection. These traits should increase their fitness in terms of survival and reproduction. On the other hand, the genetic traits which reduce the fitness of organisms are not favored. If these genetic traits are not required by organisms under the prevailing conditions, they are lost over generations.

If a bacterial species experiences reduced fitness due to the presence of antibiotic resistance genes, the bacteria without the gene would be increased in the population under the conditions of the absence of antibiotics in the environment.