To find which Antibacterial Substance best Inhibits the Growth of Bacteria.
- Words:
- 1693
- Submitted:
- Thu Jul 11 2002

... BIOLOGY COURSEWORK ANTIBACTERIAL SUBSTANCES Aim: To find which Antibacterial Substance best Inhibits the Growth of Bacteria. PLAN Introduction: The word antibiotic means 'against life'. An antibiotic is a chemical compound that is used to kill or stop the growth of infectious organisms. Antibiotics are of a 'selective toxicity' because they harm the invading organism not the host. Antibiotics only kill bacteria and do not affect viruses. There are 4 groups of antibiotics: Penicillin Cephalosporins Tetracycline Erythromycins The different types of antibiotics act against a wide range of bacteria. Penicillin is a narrow-spectrum antibiotic - they only destroy a limited number of species of antibiotics, but Tetracycline is a broad-spectrum antibiotic which acts against a broad variety of bacteria. Bacteria can become immune and resist antibiotics, so new ones have to be constantly found. Sometimes a gene in the bacteria will spontaneously change, so the antibiotic does not recognise it and the bacteria can resist the effect of the antibiotic.













