Question

We take antibiotic medicines to fight bacterial diseases. Why are antibiotics effective against bacteria but not against our own cells?

Answer 1

Huge volumes could actually be written on this: just remember that antibiotics target those parts of a bacterial cell which are specific only to prokaryotes.

Explanation:

Antibiotics are distinctly of two types: bacteriocide and bacteriostatic.

• Bacteriocides are chemicals which kill bacteria, such as penicillin or cephalosporin. Penicillin kills the bacteria by preventing cell wall formation. Disinfectants like chlorine, antiseptics, sanitisers are also bacteriocidal in action.
• Bacteriostatic agents are able to interfere with the protein synthetic machinery of bacteria, hence the bacteria may stop reproducing or its metabolic activities may slow down (our immune system can then successfully fight with such weakened organisms). Chloramphenicol, tetracycline, etc are bacteriostatic.