Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Sugar Production
Name: Lauren
Location: N/A
Country: N/A
Date: N/A

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 own enzyme.

Van Hoeck

Click here to return to the Biology Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (, or at Argonne's Educational Programs

Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory