Back to: MICROBIOLOGY 400 LEVEL
Welcome to class!
Welcome, superstar! I’m truly happy to have you here once again. You’re doing an amazing job staying consistent with your learning. Today’s lesson is exciting and very useful in science and industry. We’ll be talking about Mutation and Selection—two important tools scientists use to improve microorganisms for industrial purposes. Let’s break it down in a way that’s easy, clear, and connected to your everyday world.
Mutation And Selection
What is Mutation?
Mutation is simply a change in the genetic material (DNA) of an organism. In microbiology, scientists often cause mutations on purpose to try and improve the traits of microorganisms.
Normally, mutations happen naturally due to environmental factors like heat, chemicals, or radiation. But in the lab, scientists can also intentionally expose microbes to UV light or chemical agents like nitrous acid to force mutations. The aim is to produce a microbe that has better qualities, such as making more antibiotics or growing faster.
Think of it like changing a recipe slightly to see if it makes the food taste better. You may not always get what you want, but sometimes, one small change makes a big improvement.
Types of Mutations Used
Random Mutations: These happen by chance when microbes are exposed to mutagens (agents that cause mutations).
Induced Mutations: These are caused intentionally using UV rays or chemicals.
What is Selection?
After causing mutation, not all mutated microbes are useful. Selection is the process of identifying and keeping the best ones—those that show the improved traits we are looking for.
There are two main types of selection:
Positive Selection: Choosing microbes that show a desirable trait (e.g., producing more citric acid).
Negative Selection: Eliminating microbes that have lost a desired trait or gained a harmful one.
Selection helps scientists sort through hundreds or thousands of mutated strains to find the very few that are better than the original strain.
Imagine a yam farmer in Enugu wants a better harvest. He saves seeds from the best yams each year. One season, he tries exposing the yam seeds to heat to see if they grow bigger yams. Some come out poorly, but one grows extra large. He keeps that one and plants it again. That’s mutation and selection in real life.
Similarly, if a lab in Lagos wants yeast that produces more ethanol, they may mutate many yeast cells, then select the ones that ferment better.
Importance in Industry
Mutation and selection are very important in industries like:
Pharmaceuticals – to increase antibiotic production.
Food – to enhance flavour or reduce spoilage.
Agriculture – to improve microbes that help plants grow.
Summary
- Mutation is a change in the DNA of a microorganism.
- Scientists cause mutations to improve microbial traits.
- UV light and chemicals can induce mutations in microbes.
- Selection is the process of choosing the best mutated strains.
- These methods help improve industrial production of enzymes, antibiotics, and other useful products.
Evaluation
- What is the difference between mutation and selection in microbiology?
- Mention two ways scientists cause mutations in microorganisms.
- Why is selection important after mutation?
You’re gaining the kind of knowledge that makes you a problem-solver and innovator. Keep up the great work—you’re becoming the scientist that Africa and the world need. Stay focused and excited, because Afrilearn is here to support your journey every step of the way. See you in the next class!