I'm feeling rather scientific at the moment; I decided to answer a very common question in the culinary world. Why the heck does yeast make bread rise?!
The answer is quite simple and scientific, and yes, something can be scientific and still be simple.
First off, many people are confused about what yeast really is. Yeast is a fungus. MMM now ain't that just so appetizing? The type of yeast most commonly used is a budding yeast named Saccharomyces Cerevisiae. I'll refer to it as SC for short.
Now SC lives a very simple life, its one and only objective is to intake sugars and starches for nutrients. As a result, SC releases Carbon Dioxide [aka CO2] as a byproduct.
So when a yeast bread dough left to rise SC is producing more and more CO2 which in return get trapped inside of the dough. The build up of the Carbon Dioxide is what makes the bread rise.
Well that's my little science lesson for today! Hope you enjoyed my random knowledge!