Anantibioticis an agent that either kills or inhibits the growth of amicro organism which causes diseases in our body. Each bacteria has its own bichemical pathway and some of them even produce cell wall to protect themselves from our WBCs. The antibiotic block the biochemical pathway and destroy the cell wall of the organism, thus killing it or inhabits its growth. Since the human cells doesn't have any cell wall, antiobiotics pose no threat to human cells. But it is only affective against fungi and bacteria. Viruses can't be destroyed by using antibiotics.
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