Slide 1: Title
- Microorganisms: The Unseen Drivers of Nature
- The title signifies the important yet often overlooked role microorganisms play in our ecosystem.
Slide 2: Objectives
- The objective of this lesson is to understand microorganisms' role in food chains, comprehend the
function of decomposers, and explore the role of microorganisms in food chains and food webs.
Slide 3: What are Microorganisms?
- Microorganisms, or microbes, are tiny life forms that are too small to be seen with the naked eye.
They include bacteria, viruses, fungi, algae, and protozoa. While some can cause diseases, many play
beneficial roles such as breaking down waste, producing oxygen, and forming an essential part of the
food chain.
Slide 4: Food Chains
- A food chain represents how energy and nutrients flow through an ecosystem. It starts with a
producer (typically a plant that gets energy from the sun) and includes various levels of consumers
(animals that eat other organisms). Microorganisms often play a role in food chains as decomposers,
breaking down dead organisms and waste material to recycle their nutrients.
Slide 5: Decomposers
- Decomposers are organisms that break down dead or decaying organisms, returning essential
nutrients back to the environment. They play a critical role in the nutrient cycle. Examples include
fungi like mushrooms, and bacteria such as those found in the human gut.
Slide 6: Decomposers and Nutrient Cycling
- Nutrient cycling refers to the flow and recycling of nutrients in ecosystems. When plants and
animals die, decomposers break down their organic material and return the nutrients to the soil.
These nutrients are then available for plants to use for growth, continuing the cycle.
Slide 7: Microorganisms as Decomposers
- Many microorganisms serve as decomposers. For instance, bacteria and fungi are adept at breaking
down organic matter. They secrete enzymes that decompose the complex molecules in dead
organisms and waste material, transforming them into simpler substances that are returned to the
soil.
Slide 8: Food Webs
- A food web is a more complex and realistic representation of energy flow in an ecosystem than a
food chain. It shows multiple interconnected food chains, illustrating the variety of diets in an
ecosystem and how different organisms interact.
Slide 9: Microorganisms in Food Webs
- Microorganisms play crucial roles in food webs. For example, phytoplankton (tiny photosynthetic
organisms) form the basis of many aquatic food webs. On the other end, decomposer
microorganisms break down dead organisms and waste, recycling their nutrients. If microorganism
populations change, it can have ripple effects throughout the food web.
Slide 10: Microorganisms, Food Chains, and Food Webs: Bringing it all Together
- Microorganisms are crucial at multiple levels in food chains and food webs. They help initiate the
flow of energy as producers, and close the loop as decomposers, recycling nutrients back into the
ecosystem.
Slide 11: Fun Facts about Microorganisms
- There are more microorganisms in a handful of soil than there are people on Earth.
- Some microorganisms, like yeast, are used to make food products such as bread and beer.
- Others, like certain bacteria, help us digest our food.
- Some microorganisms can survive in extreme environments, like hot springs and the deep sea.
Slide 12: Conclusion
- Microorganisms, though small, play immense roles in our ecosystems. They are integral to the flow
of energy and nutrients, playing a part in everything from the food we eat to the air we breathe.
Slide 13: Questions and Discussion
- Open the floor for any questions or comments from the students.
Slide 14: References
- List the sources of information you used to create your presentation, such as textbooks, educational
websites, and scientific journals.