Yeast experiment

[gwuc4]

Hi all,

New member. Wanted to ask a couple questions about a recent yeast experiment. Basically. the experiment was this: Two graduated fermentation cylinders were used. In one, about 100 ml of Yeast with sugar was mixed with d- water. In the other, 100ml yeast w/out sugar (aka Glucose) was mixed with d-water. Both fermentation cylinders were then left in an incubator for a while.

Now here's where it got tricky.

There were a few questions to this experiment:
1.) which cylinder evolved CO2,
2.) what was the food source for the yeast (obvious enough),
3.)what was the point of the Non-sugar yeast, and
4.) what was the point of the vertical position of the cylinders?

So I went ahead and predicted the outcomes (which, on second thought, may have backfired on me):
1.) the yeast with sugar
2.) the CO2H
3.) to prove question 2 (the CO2H)
4.) to catalyze the CO2 production

But when I brought the cylinders out, it seemed both had evolved CO2 at the base - although the sugar yeast had also evolved a decent layer of CO2 at the very top to go along. Both cylinders were covered with the entire time as well.

So my questions are
1.)Which set of questions are correct - my predictions or the experiment (that both evolved CO2)?
2.)did I screw up the experiment?
3.)If I did not screw up, and am misreading my results, then what's the point of the nonsugar yeast in the experiment?
4.) how does a vertical position speed up CO2 production, or am I wrong to think it does?

Sorry, if I'm throwing out too many bundled questions. I'm trying to work these out it my head and am having no luck. Shouldn't have tried to predict the outcome I suppose. Please help. Thanks.

[JackBean]

CO2H is nothing

how did the CO2 in the bottom look like?

[gwuc4]

solid (crest like) with a manila-ish color.

[JackBean]

I guess you didn't mix the yeast, right? If not, the cell settle down, since they are quite heavy. But whatever it was, it was not CO2, since it is gas.