Question

E. coli is a species of bacteria that causes many different infections in humans. Certain E. coli strains have developed resistance to antibiotics, making infections with these strains difficult to treat. How do bacteria such as E. coli, which reproduce asexually, gain new traits such as antibiotic resistance?
A. by adapting to changes in environmental conditions without undergoing changes in their DNA
B. by mutating their DNA in response to environmental conditions to gain beneficial traits
C. by producing offspring with new gene assortments from genetic recombination, which increases diversity in a population
D. by undergoing spontaneous mutations when they replicate, which increases genetic variation in a population

Answer 1

Answer:

The correct answer will be option-B

Explanation:

Antibiotic resistance in bacteria develops in response to the environment in which the bacteria survives.  

The antimicrobial resistance trait is acquired by any species of bacteria through one of the two ways that are either by making changes in their DNA sequences or through horizontal gene transfer mechanisms.

In the given E. coli gained the trait to develop resistance against antibiotic by making changes in their DNA as once the gene is altered or mutated, the trait can be passed on to the offsprings.

Thus, Option-B is the correct answer.

Answer 2

B. By mutating their DNA in response to environmental conditions to gain beneficial traits.