Baker's Yeast (Saccharomyces cerevisiae) is a single celled fungus used in baking. When the fungus is added to dough, it produces carbon dioxide as it consumes sugar. The carbon dioxide gas produced is what makes dough rise when preparing dough for baking. A different strain, Brewer's yeast, is used to make wine and beer. Both strains produced alcohol when the yeast consumes sugar in an anaerobic environment. Brewer's yeast is adapted for wine and beer making while baker's yeast is adapted for baking.

S. cerevisiae is also a very important model organism in biology. Biologist have studied yeast for decades and it has taught us a great deal about genetics, gene expression, cell division, proteins and so much more.

Yeast cells will create a bud, a small protrusion, as it divides to make a new cell. Some budding yeast can be seen at the end of the video.

Magnification of each shot is shown at the bottom right.