(b) : Antibiotics are not capable of curing any disease. Antibiotics are those substances that destroy or inhibit the growth of micro-organisms, particularly disease producing bacteria and fungi. The term antibiotic was introduced by Waksman in 1942 . Antibiotics are obtained form micro-organisms (especially moulds) or synthesized. Common antibiotics include penicillin, streptomycin and tetracyclines. They are used to treat various infections but tend to weaken the body's natural defence mechanisms and can cause allergies. Overuse of antibiotic can lead to the development of resistant strains of micro-organism.