The main reason why antibiotics could not always treat the bbacteria-mediated diseases is

Options

A. insensitivity of the individual following prolonged exposure to antibiotics
B. inactivation of antibiotics by bacterial enzymes
C. decreased efficiency of the immune system
D. the development of mutant strains re

Answer

D

Explanation

A major problem in the treatment of bacterial mediated diseases is that many bacteria have been found to show resistant to antibiotics. The emergence of antibiotic -resetant bacteria is closely linked to the extent that antibiotics are used in humans and items of human diet. resistant strains may appear rapidly or slowly . according to the amount or type of antibiotic used . Bacteria occur in such large number of there is a high chance of a mutant individual eventually appearing in the population . As soon as it does, use of the antibiotic to which it is resistant will give it a selective advantage over non - resistant types and it will multiply and eventually bcomes the dominant type . Antibiotics may also be destroyed by enzymes inside the cells being targetted . A well - known and important example is the group of enzymes known as penicilins and cephalosporins.