ELI5: Explain Like I'm 5

Start point (yeast)

Okay, so let's talk about something called yeast. Yeast is a tiny living thing that's so small you can't see it without a special tool called a microscope. It's kind of like a plant, but it's more like a fungus.

Now, yeast is really important because it helps make bread and other yummy treats. Have you ever had a muffin or a cupcake? Well, yeast is what makes them super fluffy and delicious.

But how does yeast work? Well, when you're making bread or something like that, you have to mix yeast with some other ingredients like sugar and water. Then, you have to let the mixture sit for a while.

After a little bit, the yeast will start to eat the sugar in the mixture. Yep, that's right - yeast eats sugar just like we eat our favorite snacks. As the yeast eats the sugar, it starts to make something called carbon dioxide.

Carbon dioxide is a gas that's kind of like the air we breathe. But, the yeast makes a LOT of it all at once! So, as the yeast grows and makes more and more carbon dioxide, it starts to make the bread dough rise.

That's why when you see a blob of dough, sometimes it's really big and puffy. That's because the yeast is working hard to make it rise. And after that, you can bake it in the oven and get some yummy bread or cake!
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