The purpose of this lab was to have students observe passive transport of sugar
and starch molecules through a membrane. Dialysis tubing was meant to
represent the membrane. The tubing was opened, filled with 10-15 mol and
starch and sugar solution, tied shut, and then placed in a cup of water
overnight. The water inside and outside of the bag was tested the next day
for presence of sugar and starch molecules. The water inside of the bag
should have tested positive for both sugar and starch. The water outside
the bag should have tested positive for sugar, but not for starch. The starch
molecules were too big too pass through the membrane. The order of
molecules used in the lab from biggest to smallest were: starch, sugar,
water.