1. Your guide to successful experimentation!
BUBBLE BLOWING FUNGI
Your guide to successful experimentation!

2. There’s a Fungus Among Us!
Sometimes it can cause some irritating problems, but…

3. Without it there’d be no…

4. Yeasts are living organisms, just like us...sort of.
They process food for energy.
They grow.
They reproduce.
They have an optimum temperature for cellular activity.

5. But yeast is a decomposer, just like other fungi…

6. Yeast is one kind of sac fungi.

7. Fermentation in Yeast Yeast needs sugar for energy.
The following chemical equation shows how yeast breaks down table sugar (sucrose):
C12H22O11 + H2O → 4C2H5OH + 4CO2 + energy
(or in English…)
sugar + water → ethanol + carbon dioxide + energy

8. Baking with Yeast
Baker’s yeast is a special kind of yeast used in…you guessed it...baking!
The carbon dioxide gas forms bubbles that are trapped in the bread dough.
As these bubbles form, the dough rises.
Why do you think recipes tell you to let the dough rise in a warm place?
What do you think happens when you bake the bread at high heat in the oven?

9. Now for the problem of the experiment…
What is the effect of temperature on yeast fermentation?
Write the problem on your experimental design diagram.

10. Variables
How are you going to measure the amount of fermentation of the yeast???
What variable will you be manipulating?
Decide which is the independent variable and write that on your diagram.
Decide which is the dependent variable and write that on your diagram.

11. Hypothesis
Now write your hypothesis on your diagram. Remember to use the if…then format.

12. Procedure
Get together with your group members to compare your diagrams. Decide which answers are the best and design your experiment.
Use the materials provided to write your procedure. Leave a space after each step so you can add more later if you need to. Check the questions on the Investigative Lab Report Format to make sure you have remembered everything.