Question

Antibiotic resistance occurs when an antibiotic has lost its ability to effectively control bacterial growth. In other words, the bacteria are “resistant” and continue to multiply in the presence of therapeutic levels of antibiotic. Which statement best explains this natural phenomenon in terms of Darwin’s theory of natural selection.
A. The antibiotics caused certain groups of bacteria to suddenly start producing enzymes that destroyed the antibiotic before it could harm the bacteria.

B. When an antibiotic is used, bacteria that have a natural variation for resistance to the antibiotic have a greater chance of survival.

C. Although susceptible bacteria are killed or inhibited by an antibiotic, any offspring they produced before they died will be resistant to the antibiotic.

D. The need to adapt or die caused some bacteria to become resistant to the antibiotic. This acquired resistance was passed into the future bacteria populations making them resistant.

Answer 1

Answer;

B. When an antibiotic is used, bacteria that have a natural variation for resistance to the antibiotic have a greater chance of survival.

Explanation;

Antibiotic resistance is a consequence of evolution via natural selection.

The antibiotic action is an example of environmental pressure to bacteria, therefore; those bacteria which have a mutation allowing them to survive will live on to reproduce.

They will then pass this trait to their offspring, which will be a fully resistant generation.