This is the experiment I did: our class took 6 sugars,
placed them in test tubes and put three drops of yeast in each test tube.
we then placed them in the incubator for one day and the next day looked
at our results. the purpose was to find out with sugar would produce the
most carbon dioxide. two of the sugars that we tested were LACTOSE and
STARCH. my question is, why are lactose and starch the only sugars who
didn't produce any, or very very little, carbon dioxide? and how is this
process related to glycolysis?
Bacteria and yeast are very efficient with their enzyme systems. They don't
make enzymes they can't use. Yeast don't have the enzymes necessary to
metabolize lactose. Starch is a complex sugar and yeast needs certain
enzymes to break starch down into sugar. Every chemical reaction needs its
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Update: June 2012