How does the process of fer mentation help bread rise?

2 In the fermentation process, the yeast produces CO2 which, as bubbles, makes the bread more porous, and 'rise'.

Alcoholic Fermentation causes bread to rise.

Carbon Dioxide.

Yeast turns some of the sugar in bread dough into alcohol and carbon dioxide. The carbon dioxide fills the bread with a lot of little bubbles. That makes it easy to eat. Without yeast bread would be...

The yeast is a living organism and therefor needs to eat when the yeast eats it makes a byproduct called carbon dioxide (CO2) it is this gas that makes the bread rise.