Do antibiotics kill all form of infection at once?

Answer 1

No, antibiotics fall into two categories: bacteriostatic and bacteriocidal. Bacteriostatic antibiotics simply slow bacteria to a halt but do not actively "kill" bacteria. An example is Tetracycline - which binds to the bacterial 30s protein of the ribosome and stops protein synthesis. Bacteriocidal antibiotics do indeed cause destruction of the bacteria. Penicillin is a good example of this. By inhibiting peptidoglycan repair, the osmotic damage caused by the "leaky" cell membrane causes enough damage to swell the bacteria and lyse the cell.