This year when it was time to teach the fungi in our curriculum, I wanted to do a make a mold terrarium activity/experiment that my students could relate to. I wanted to show them that all organisms on Earth are important and all organisms on Earth play a role in the ecosystem.
When you say the word “fungi” to many students, their usual response is that they are gross and they are not important. Our very lives and the lives of every organism on Earth, depend upon the role played by the fungi. They are decomposers and we cannot live without them.
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Make a Mold Terrarium – Intro to Fungi and Mold
Mold and fungi are both living things that belong to a group called the kingdom Fungi. They’re a bit different from plants and animals because they don’t have leaves or flowers and can’t move around independently. Instead, they grow using long, thread-like things called hyphae. These hyphae spread out a lot, helping the fungus get nutrients from its surroundings.
Mold is a specific kind of fungus that likes to grow in warm, damp places. You might see mold on old food, wet walls, or even in your shower. Mold can come in different colors, like green, black, or white. It can also feel fuzzy or slimy.
Some types of mold can make people sneeze or have trouble breathing.
There are other types of fungi, too, like mushrooms, yeast, and truffles. Mushrooms are the parts of fungi that you can see growing above the ground. Yeast is a tiny fungus made up of just one cell, and it’s used to make bread rise. Truffles are special fungi that grow underground and are really yummy.
Fungi do important things in nature. They help break down old plants and animals and can even make chemicals that kill bad bacteria. Some fungi are used to make medicines, like penicillin, which helps people get better when they’re sick.
Let’s look at some ways mold and fungi are alike and different:
- Both mold and fungi belong to the Fungi group.
- They both grow using long, thread-like hyphae.
- They both get nutrients from their environment.
- Both types can be bad for us, but some are helpful.
- Mold is a kind of fungus, but not all fungi are mold.
- Mold likes warm, wet places, while other fungi can grow in different spots.
- Mold can be different colors, but most fungi are white or brown.
- Mold can be fuzzy or slimy, while other fungi can feel different.
- Some mold can make us sneeze or have trouble breathing, but most fungi don’t harm us.
Important Points About Fungi
It made it very easy for me to teach the important points about the fungi:
1. Fungi are “plant-like” but do not belong to the plant kingdom. They belong to a separate kingdom…the Fungi Kingdom.
2. Fungi are not true plants because fungi are heterotrophs. They do not contain chloroplasts with chlorophyll and therefore cannot carry out photosynthesis.
3. Fungi are not true plants because they do not possess true roots, stems, and leaves.
4. Fungi are not true plants because they have a cell wall composed of chitin. True plants have a cell wall composed of cellulose.
5. Fungi are decomposers, a role that is absolutely essential in our ecosystem.
6. In the process of decomposition, the essential elements for life (carbon, hydrogen, nitrogen, phosphorus, etc.) are returned to the ecosystem so that they may be used in the bodies of new organisms.
7. Fungi are an important food source. We consume many varieties of mushrooms, and the yeasts are important in the baking industries.
8. Thank goodness Walther Flemming noticed that the Staph bacteria he was attempting to grow was inhibited by the presence of a pesky green mold! Hooray for penicillin!
Make a Mold Terrarium
We have created some worksheets to use as your children make a mold terrarium. The request box is below.
What could I do to make the fungi more interesting for my students? I decided we would build mold terrariums. I wasn’t exactly sure how the idea would go over with my students, but I decided to give it a go anyway. MY STUDENTS LOVED IT! On lab day I gathered the necessary materials, I wore my favorite t-shirt that has a mushroom on the front with the caption “Hey! I’m a Fun-Guy!”, and we began to make mold terrariums!
No fancy materials are required. You only need a clear container, water, and some left over foods. Have your child first propose a hypothesis.
Examples: I think that food X will mold first. I predict that it will take X days for the first signs of mold to appear. I predict that fresh foods will mold faster than processed foods.
Use the request box below to receive the worksheets that accompany this activity.
To set up the terrarium, simply choose the foods you want to test and place them in a clear container. You want to use a container that is “see-through” and also a container that you don’t mind throwing away at the end. A large glass pickle jar would be perfect! Moisten the food, and then place it in the container. Place the container in an area out of direct sunlight.
From start to finish, I would allow at least 12 days. Nothing much happens at first, but when the molds start to grow…. WOWEE!…they really take off. Enjoy these pictures!!
As You Make a Mold Terrarium, You Might Enjoy These Items
Day 1: Setup
Day 3: The cucumber was the first to start showing mold.
Day 4: The cheese is starting to get “iffy.”
More About Bread Mold
Bread mold is a type of fungus that is commonly found on bread. It is a member of the genus Rhizopus, and it is characterized by its long, branching hyphae. These hyphae are multinucleated, which means that they have multiple nuclei in each cell. This allows bread mold to grow and spread quickly.
The Structure of Bread Mold
Hyphae: The hyphae are the thread-like structures that make up the body of bread mold. They are made up of cells that are joined together by cross walls. The hyphae can grow up to several centimeters long, and they can branch out to form a network that covers the surface of the bread.
Sporangia: The sporangia are the reproductive structures of bread mold. They are sac-like structures that contain spores. The spores are released from the sporangia and can be carried by air or water to new locations. When the spores land in a suitable environment, they germinate and produce a new bread mold colony.
Rhizoids: The rhizoids are root-like structures that anchor bread mold to the surface of the bread. They help to absorb nutrients from the bread. It is commonly known as black bread mold, pin mold, or white bread mold. Rhizopus can grow on a variety of organic materials, including bread, fruits, vegetables, and decaying plant matter. It can also cause diseases in humans and animals.
Cilia: The cilia are hair-like structures that help bread mold to move. They are also used to sense the environment.
Reproduction: Bread mold can reproduce both sexually and asexually. Sexual reproduction occurs when two hyphae of different mating types come into contact with each other. This results in the formation of a zygosporangium, which contains a zygospore.
The zygospore can survive for long periods of time in unfavorable conditions. When conditions become favorable, the zygospore germinates and produces a new bread mold colony. Asexual reproduction in bread mold occurs by the formation of sporangia. The spores are released from the sporangium and can be carried by air or water to new locations. When the spores land in a suitable environment, they germinate and produce a new bread mold colony.
Rhizopus fungi reproduce both sexually and asexually. Sexual reproduction occurs when two hyphae of different mating types come into contact with each other. This results in the formation of a zygosporangium, which contains a zygospore. The zygospore can survive for long periods of time in unfavorable conditions. When conditions become favorable, the zygospore germinates and produces a new Rhizopus fungus.
Asexual reproduction in Rhizopus fungi occurs by the formation of sporangia. Sporangia are sac-like structures that contain spores. The spores are released from the sporangium and can be carried by air or water to new locations. When the spores land in a suitable environment, they germinate and produce a new Rhizopus fungus.
Nutrition: Bread mold is a heterotroph, which means that it obtains its nutrients from other organisms. It breaks down the carbohydrates in bread using enzymes. The enzymes release simple sugars that the bread mold can absorb.
Growth: Bread mold can grow rapidly in moist, warm environments. The ideal temperature for growth is 77°F (25°C). Bread mold can also grow in cooler temperatures, but it will grow more slowly.
Sensitivity to light: Bread mold is sensitive to light. It grows best in dark or dimly lit environments. If bread mold is exposed to bright light, it will stop growing and may even die.
Rhizopus fungi are important in the environment because they help to break down dead organic matter. They also produce enzymes that can be used in industrial applications, such as the production of food and beverages. However, Rhizopus fungi can also be harmful to humans and animals. Some species of Rhizopus can cause infections in the respiratory system, skin, and eyes. In severe cases, these infections can be fatal.
This post is co-authored by Michelle Moody and Amy Brown. Amy is a high school biology and chemistry teacher of 28 years. She absolutely loves Biology and turning kids on to science!! It is such a joy when her excitement for biology and nature is contagious, and her students catch it!
Michelle is the owner of The Homeschool Scientist and holds an MA in early childhood development and education. She is pursuing a post-baccalaureate in biology. She homeschooled her children and taught kindergarten in the traditional classroom and robotics in Bangladesh.