Do yeast release carbon dioxide gas causing the bread dough to rise?

Yes, that's exactly right! Yeast releases carbon dioxide gas, which causes bread dough to rise.

Here's how it works:

1. Yeast eats sugar: Yeast is a living organism that feeds on sugars (like those found in flour).

2. Fermentation: During this process, yeast breaks down sugar into carbon dioxide and alcohol.

3. Trapped gas: The carbon dioxide gas produced gets trapped in the gluten network of the dough.

4. Rise: This trapped gas causes the dough to expand and rise.

The more yeast and sugar you use, the more carbon dioxide is produced, and the higher your bread will rise.