Antibiotics and Antibiotic Resistance (Leaving Cert Biology): Revision Notes
📚 Revision Notes
Antibiotics and Antibiotic Resistance
infoNote
Antibiotics are substances produced by micro-organisms that kill or prevent the growth of bacteria and fungi.
Antibiotic Resistance
How Resistance Develops:
- When an antibiotic is first used, it kills all of the bacteria in an organism.
- Over time, a mutation may occur in one bacterium, making it resistant to that antibiotic.
- The gene for antibiotic resistance is found on the plasmid of the bacterium.
- As the antibiotic-sensitive bacteria are killed, the resistant bacteria survive, replicate and spread the resistance gene.
Multi-Resistant Bacteria:
- Some bacteria has developed resistance to most, if not all, antibiotics.
- These are called multi-resistant bacteria, such as MRSA (commonly known as a 'superbug').
Causes of Antibiotic Resistance:
- Over-prescription of antibiotics by doctors.
- Failure to complete the full course of antibiotics by patients.
- Overuse of antibiotics in animal feed, which can lead to the development of resistant strains in livestock.