Back to: MICROBIOLOGY 400 LEVEL
Welcome to class!
Hi brilliant star! I’m super glad to see you back in class today. You’re doing so well, and I’m really proud of your commitment to learning. Today, we’ll talk about how microorganisms interact with one another and with other living things in the environment. Just like in a busy Nigerian market where people cooperate, compete, or sometimes clash, microbes also have different types of relationships. These include symbiosis, antagonism, and competition. Let’s break them down together in a way that’s clear and very relatable.
Symbiosis, Antagonism, Competition
Symbiosis
Symbiosis means “living together.” It refers to close and long-term interactions between two different organisms. These relationships can benefit both organisms, one of them, or even harm one while benefiting the other.
Types of Symbiosis:
Mutualism – Both organisms benefit.
Example: Rhizobium bacteria in the roots of legumes like beans and groundnuts. The bacteria fix nitrogen for the plant, and the plant gives food and shelter to the bacteria.
Commensalism – One organism benefits while the other is not affected.
Example: Bacteria that live on the surface of human skin feeding on dead skin cells without harming or helping the person.
Parasitism – One organism benefits, and the other is harmed.
Example: Plasmodium falciparum, the parasite that causes malaria, lives in humans and takes nutrients from them, causing illness.
Antagonism
Antagonism is when one microorganism harms or inhibits the growth of another. This is common in nature and even useful in medicine.
Example: Penicillium fungi produce penicillin, a substance that kills or stops the growth of certain bacteria.
Another example is Lactobacillus bacteria producing acids that kill harmful microbes in fermented foods like ogi (pap).
This behaviour is important in the production of antibiotics and maintaining balance in microbial communities.
Competition
Competition happens when two or more organisms struggle for the same limited resources—like space, nutrients, or oxygen.
In soil, two bacterial species may compete for the same food source.
In a nutrient-poor pond, algae and bacteria may compete for light and minerals.
Microbial competition ensures that only the fittest organisms survive, which keeps ecosystems balanced and healthy.
Real-life Connections in Nigeria
Farmers often rotate crops like maize and legumes to support mutualistic soil microbes.
Traditional fermentation methods in Nigerian kitchens use microbial antagonism to prevent spoilage.
In crowded environments, like urban Lagos, understanding microbial competition helps in designing better waste and disease control systems.
Summary
- Microorganisms interact in various ways: symbiosis, antagonism, and competition.
- Symbiosis includes mutualism, commensalism, and parasitism.
- In mutualism, both organisms benefit (e.g. Rhizobium and legumes).
- In commensalism, one benefits while the other is unaffected.
- In parasitism, one benefits while the other is harmed (e.g. Plasmodium in malaria).
- Antagonism involves one microbe inhibiting another (e.g. Penicillium producing antibiotics).
- Competition occurs when organisms fight for the same resources.
- These interactions affect health, agriculture, and environmental balance.
- Microbial relationships are common in Nigerian soil, food, and water systems.
Evaluation
- Describe the three main types of symbiosis with examples.
- What is microbial antagonism and why is it important?
- How does microbial competition affect ecosystems?
Keep feeding that sharp brain of yours with knowledge—your future is looking so bright. Remember, Afrilearn is always here to support your learning journey. See you in the next exciting lesson!