Antibiotic Resistance
Bacteria evolve resistance when antibiotics are overused.
About this topic
Antibiotics kill bacteria or stop them growing, but random mutations can make some bacteria resistant. When antibiotics are used, resistant bacteria survive and reproduce, passing the gene on, even to other species via plasmids: natural selection in action. Overuse and not finishing courses speed it up.
Resistant "superbugs" like MRSA and drug-resistant TB are a major health threat. Solutions include using antibiotics only when needed, completing courses, hygiene, and developing new drugs. Antibiotics don't work on viruses.
Imagine a bacterial infection of a million bacteria, with one that happens to carry a resistance mutation. If a patient stops taking antibiotics early, the weakest bacteria die while the resistant survivor multiplies. MRSA is a notorious example, resistant to methicillin and many other drugs, and is a problem in hospitals. Resistance genes can spread between bacteria on plasmids.
To slow resistance, doctors should prescribe antibiotics only for bacterial infections, patients should finish the course, and farmers should avoid routine use in healthy animals. Antibiotics do nothing against viruses such as colds and flu. A major misconception is that your body becomes resistant to antibiotics; actually the bacteria evolve resistance. Researchers are seeking new antibiotics and alternatives such as phages.
Key ideas
- Resistant mutants survive
- Finish prescribed courses
- MRSA is a superbug
Quick check
Use cases: where Antibiotic Resistance helps
- Homework: review the key idea behind Antibiotic Resistance before you start a problem set.
- Exam revision: use the quick check to test whether you can recall Antibiotic Resistance without notes.
- Visual learning: play with the interactive lab to see how Antibiotic Resistance changes when you adjust its inputs.
- Teaching a friend: explain Antibiotic Resistance in your own words, then compare your version with the key ideas.
Biology underpins medicine, farming, conservation and biotechnology.
Frequently asked questions
What is Antibiotic Resistance?
Bacteria evolve resistance when antibiotics are overused.
What will I learn in Antibiotic Resistance?
Resistant mutants survive. Finish prescribed courses. MRSA is a superbug.
Is Antibiotic Resistance part of Biology?
Yes. It is one of 150 Biology topics on LearnViz HighSchoolEdu, with 3 key ideas, a live animation and a quick check.
Does the Antibiotic Resistance lab work on a phone or tablet?
Yes. The animation resizes to fit your screen and supports touch, so you can drag, tap and slide with your finger.
How should I study Antibiotic Resistance?
Read the summary and key ideas first, play with the interactive lab to see the idea in motion, then answer the quick check. If you get a question wrong, go back to the key idea it tests.
Do I need an account, and is my progress saved?
No account is needed. Marking a topic as learned is saved in your own browser, so it stays on that device and is not sent to a server.