Question

Explain antibiotic resistance observed in bacteria in light of Darwinian Selection theory.

Answer 1

Antibiotic resistance occurs when germs like bacteria and fungi develop the strength to defeat the drugs devised to kill them. The germs are not killed and resume to grow. Infections generated by antibiotic-resistant germs are difficult and impossible to treat.

Complete answer:
According to Darwin's natural selection theory, only those organisms that can adjust to the changing environment will sustain. Those organisms that cannot squeeze to the change in their environment will be excluded. So, organisms manage to obtain new features to survive and maintain their culture. An example of such selection is antibiotic resistance in bacteria. A bacterial population was developed on an agar plate that contained antibiotic penicillin. The colonies that were susceptible to penicillin died. Whereas one or few bacterial colonies that were immune to penicillin survived. However, with time the bacteria uncovered methods to fight the antibiotic and persist in the presence of penicillin. This is because these bacteria had experienced a chance in mutation. This emerged in the evolution of a gene that caused them to be resistant to penicillin drugs. Hence, the resistant bacteria multiplied swiftly as compared to non-resistant (sensitive) bacteria. Hence it increased the number. As a result of this, penicillin-resistant bacteria grew and remained because of the environment that chose these over the others.

Note: Darwinian selection theory proposes that the environment chooses organisms with valuable variation over those which do not have beneficial variations. It is essential because, in a dynamic environment, these organisms are better accommodated to survive.