Read this passage and study the chart. Then do
Numbers 26 and 27.
An experiment was done to compare the conditions
necessary for growth and cell division of yeast and of
algae. Beakers of sterile water containing algae or
yeast cells were subjected to different conditions:
darkness with sugar, darkness without sugar, light
with sugar, and light without sugar. After three
days, the beakers were checked to see whether the
cells had multiplied.
Algae
Yeast
Sugar
Dark
No Sugar
Light
Sugar
No Sugar
✓-cell growth and division
26
Why did the scientist use sterile water in the
experiment?
F to avoid the spread of infectious disease
G to exclude cells that were not being
studied
H because the natural environments of
algae and yeast are sterile
J because only sterile materials are
allowed in science laboratories