Slime Mold : Reproduction

Ten Things I Like About... Podcast

Summary: Where does slime mold come from? Join Kiersten as she explains how slime mold reproduces.

For my hearing impaired listeners, a complete transcript of this podcast follows the show notes on Podbean

Show Notes:

“Slime Mold Reproduction” Brad Renner, University of Wisconsin-La Crosse. bioweb.uwlax.edu

“Slime Mould,” by Thomas J. Volk, in Encyclopedia of Biodiversity, 2001. https://www.sciencedirect.com

“The Blob: Slime Molds.” Herbarium Utah State University. https://www.usu.edu

Transcript

(Piano music plays)

Kiersten - This is Ten Things I Like About…a ten minute, ten episode podcast about unknown or misunderstood wildlife.

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Welcome to Ten Things I Like About… I’m Kiersten, your host, and this is a podcast about misunderstood or unknown creatures in nature. Some we’ll find right out side our doors and some are continents away but all are fascinating.

This podcast will focus ten, ten minute episodes on different animals and their amazing characteristics. Please join me on this extraordinary journey, you won’t regret it.

This is episode number five of slime mold and the fifth thing I like about slime mold is how it reproduces.

Some of you may be wondering where exactly do slime molds come from? Well, when a mommy slime mold and a daddy slime mold love each other very much…. No, no just kidding. Slime molds are delivered by a stork….Okay, it’s out of my system. Now, seriously. Slime molds reproduce through spores. These spores can lay dormant in soil for many years. This is why it seems like slime molds arise out of nowhere. They were just tucked down into the soil waiting for the right time to grow. As we’ve discussed in previous episodes, that usually happens after a nice warm rainy season.

A general life cycle for slime mold follows a basic pattern. It begins with a stalk-like structure with a sporangium on top. Spores are held inside this sporangium and when they are mature and the environment is just right, the spores are released. The spores will germinate into an ameboid cell. These cells enter into the feeding stage for a certain period of time. When the slime mold enters the mature stage it will begin preparing to fruit and you’ll see young sporangium fruiting. Then we arrive back at the stalk-like structure where we began. This pattern holds true for both plasmodial and cellular slime molds with some slight differences.

The life cycle of plasmodial slime molds includes two stages. When those perfect conditions happen the spores resting in the soil germinate and release small, motile cells. Two of these cells will get together and form a shapeless mass, the plasmodium. Which is, as we know, a multinucleate mass of protoplasm. This is the feeding and creeping stage of the organism.

The second stage is triggered by drying weather. If the plasmodium begins to dry out too quickly or is starved, it forms a survival structure called sclerotium. This is a hard-walled mass that will protect the cells within until environmental conditions improve. Inside, spores are created waiting for favorable weather to return. And when it does the plasmodial slime mold will be on the prowl again.

Now, think back to that first slime mold episode with me. In that episode we learned that there is more than one kind of slime mold. We just discussed reproduction of plasmodial slime mold, so let’s take a gander at cellular slime mold reproduction.

Cellular slime molds reproduce in a similar manor as plasmodial slime mold with one major difference. Cellular slime molds remain individual cells with one nucleus. The individual slime molds, also known as slime mold “slugs”, will crawl along substrate at 1 millimeter per hour leaving behind a trail of chemicals. These chemical trails will attract other slime mold slugs. When many of them finally come together they form a pseudoplasmodium. It’s a pseudoplasmodium because the cells remain separate with their one nucleus a piece. As the slugs aggregate about one-third of them will come together to create a fruiting body. A fruiting body is a stalk-like structure with a sporangium on top filled with spores. When the weather is moist enough and at just the right temperature, the spores are released and cellular slime molds are released to start the cycle all over again.

Once again slime mold is blowing my mind and I hope you feel the same way because reproduction is my fifth favorite thing about this amazing protist.

If you're enjoying this podcast please recommend me to friends and family and take a moment to give me a rating on whatever platform your listening. It will help me reach more listeners and give the animals I talk about an even better chance at change.

Join me next week for another episode about slime mold.

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This has been an episode of Ten Things I like About with Kiersten and Company. Original music written and performed by Katherine Camp, piano extraordinaire.