InvestigateWhat are some
characteristics of yeast?
Yeast
are tiny organisms. Each is a single cell. In a warm place
with sugar and water, yeast grow quickly. Bakers put yeast in
bread dough to help the bread to rise.
Materials
What
to Do
Shake
spoonful
of yeast on the
watermelon slice.
watermelon
slice
yeast
spoon
plastic
bag
Put
the watermelon
slice in the bag.
Seal
it and set it
in a warm
place.
Use a hand
lens
to observe
the
yeast.
After 1 hour, observe
the yeast. Describe
any changes.
hand lens
microscope
and
microscope slide
The
yeast you
observed are classified as
fungi, based on
their properties
Observe
the yeast 2 more times.
Describe any changes.
Time
Appearance
of Yeast on
Watermelon Slice
After 1 hour
After 2 hours
After 3 hours
Observe a tiny amount of the
yeast with a microscope. Notice
that the cells are similar to each
other. Draw your observations.
What tiny organisms
did you see through
the microscope?
Explain Your Results
1. Did the appearance of the yeast
change? How?
2. Yeast arenotclassifiedin
the plant kingdom or
the animal kingdom. Why?
3.Infer
Which kind of bread has yeast added to its
dough, flat bread or loaf
bread? Why do you
think so?
Does
yeast need light to
grow? Develop a plan
to answer this or other
questions you may have.
spoonful
