Yeast Metabolism Lab Mrs. Zimmerman 10/22/10

Photosynthesis 6 CO H 2 O  C 6 H 12 O O 2 Energy from sunlight

Respiration

Cellular Respiration C 6 H 12 O O 2  6 CO H 2 O + energy Oxygen Glucose Carbon Dioxide Water Energy

Yeast Unicellular Eukaryotic (like us) Kingdom Fungi Hetero-trophic (like us) Can produce energy anaerobically (without O 2 ) -> called “Fermentation” Saccharomyces cerevisiae

Alcoholic Fermentation Some organisms, including yeast, can create energy without oxygen, but produce the toxin ethanol as a by-product. Beer and wine Bread

Alcoholic Fermentation

What happened there? The alcohol gets burned off when bread bakes, which is why it’s ok to eat. Yeast + C 6 H 12 O 6  6 CO 2 + ethanol + energy

Back to the lab… Yeast + C 6 H 12 O 6  6 CO 2 + ethanol + energy Independent variable Dependent variable

Hypothesis Make a prediction about which treatment will produce the most carbon dioxide… –Yeast + water? *Control –Yeast + glucose? –Yeast + Splenda?

Graphing your results WATERGLUCOSESPLENDA Circumference of Balloon (cm)