Grade 9 Science Fair Project - "The Reactive Science of the Yeast Plant"

The purpose of this science fair project is toBegin by creating a yeast culture. Add a tablespoon of
demonstrate how the yeast plant reacts with certaindry yeastto one cup of warm water. Stir the mixture
foods. For example, yeast is used to raise breads.until the yeast has all dissolved. Pour one tablespoon of
Yeast is a single celled plant that is a type of fungus.this solution into each of the 12 cups in the muffin tin.
Yeast is unable to manufacture food because it doesStep #2:
not contain the chlorophyll characteristic of greenCreate a note card diagram so you can keep track of
plants. Yeast cells change certain foods into alcoholwhich foodyou place in each muffin tin. Do NOT place
and carbon dioxide when they breathe. This carbonany food into the first muffin tin so that it can act as
dioxide is what causes bread dough to rise. Thisthe "control" group in this experiment. Refer to the
science fair project also involves building a contraptionlisting of food samples in the material section. Place 1/4
that will measure the rate of reaction of yeast and ateaspoon of flour into the second cup. Place 1/4
sugar solution.teaspoon of the table sugar into the third cup. Repeat
Hypothesisthis process through the rest of the food samples in
Yeast reacts at a faster rate with certain types ofthe materials section.
foods.Step #3:
Variables:Place the muffin tin in an oven that is at 150 degrees
Food type sampleFahrenheit.
Temperature of waterCheck the muffin tin after three minutes. Record which
Materials:food samples have created bubbles due to the carbon
Project #1:dioxide reaction from the yeast. Which food samples
Yeastreacted right away and which did not? Record your
Warm Waterresults.
Tablespoon, TeaspoonStep #4:
Muffin tin built for 12 muffinsPlace the muffin tin back in the oven and check it after
12 Note cardsfive moreminutes. Record your results.
MarkerProject #2:
Notebook paperStep #1:
12 StrawsAlmost completely fill the test tube with one
Oventablespoon of yeastand three tablespoons of sugar in
Food samples you will add:a cup of warm water. Insert the small tubing through
1. Flourthe stopper. Place the stopper on the test tube.
2. Table sugarStep #2:
3. Brown sugarFirst fill the tall water glass with cold water that is at 35
4. Powdered sugardegrees
5. Sugar substitutesFahrenheit. This temperature needs to be maintained.
6. CornstarchYou can add ice to the water to keep it chilled. You
7. Saltcan monitor the water temperature using a cooking
8. Milkthermometer. Place the test tube into the tall water
9. Chopped meatglass. Place the other end of the small tubing into the
10. Cooking oilempty beaker. Let five minutes pass.
11. Pancake syrupStep #3:
Project #2:Fill the graduated cylinder with water and turn it upside
Small tubingdown inthe beaker. Make sure the open end of the
Test tubegraduate cylinder covers the end of the small tubing.
Rubber stopperStep #4:
Cooking thermometerCarbon dioxide will have formed in the test tube. This
Tall water glasscarbondioxide will replace the water in the graduate
Graduate cylindercylinder. Record the volume of gas created every 30
Yeastseconds for 15 minutes. Repeat this experiment at
Sugarvarious temperatures in the tall water class.
Cup of Warm waterSummary of Results:
BeakerCreate a chart that displays the reaction rates for the
SCIENCE EXPERIMENT NSTRUCTIONS:different food samples. Plot a graph that shows the
Project #1:amount of time versus the volume of carbon dioxide
Step #1:created.