Purpose: The purpose of this investigation is to demonstrate the process by which some cells burn a fuel without oxygen, a process called anaerobic cell respiration. The particular type of anaerobic respiration observed in this experiment is alcohol fermentation.
Materials and Methods: Materials required for this experiment include yeast cells, brown sugar, a 150 ml beaker, stirring rod, and a fermentation tube.
Mix brown sugar, yeast, into water in the 150 ml beaker. Stir the mixture for several minutes.
Experiment: Pour the mixture into a fermentation tube. Tilt the tube so that the mixture moves into the blind end of the apparatus. Initially a vacuum will hold the mixture up in the blind end of the tube. Eventually the yeast cells will burn the sugar and produce a gas which pushes the mixture back into the bulb of the fermentation tube.
Your experiment should resemble the model shown below:
Conclusion: Distinguish between aerobic and anaerobic respiration.
What is the gas that collects in the blind end of the fermentation tube?
What is alcohol fermentation?
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