Materials and Equipment
•12 tall, slim glasses or clear plastic containers (water bottles are good)
•4 bendable straws
•4 straight straws (stirrers)
•Modeling clay or play dough
•Limewater
•1 box of glucose tablets (available at your local pharmacy; you need 6 5-gram tablets)
•Yeast (12 tablespoons total)
•Water
•White sugar
•Corn syrup
•Flour
•Vegetable oil
•Stove
•Over gloves
•Measuring cups and spoons
•Small pot
Experimental procedure
Make a 10% glucose solution by dissolving 6 5-gram glucose tablets in 300 ml of (about 1.25 cups). Gentle heating and stirring will help to dissolve the tablets. After the tablets are fully dissolved, boil the solution gently for five minutes to eliminate all oxygen in the glucose. Warning: be careful with hot stove, pot and liquid!!
Use oven gloves to remove the small pot of glucose from the stove. Allow it to cool (feels slightly warm to the touch).
Add 2 teaspoons of yeast to glass/plastic container. Pour the boiled glucose solution into the same container. Use a spoon/straw to gently mix.
Carefully pour half tablespoon of vegetable oil into the container so that it rests on top of the yeast- mixture to keep oxygen from entering the system.
Insert one bendable straw into the other bendable straw.
Bend the ends of both straws at a 90-degree angle. Place the end of one straw in the mouth in the plastic/glass container you just prepared. Secure it in place with modeling clay or play dough.
Fill a second plastic/glass container about three-fourths full of limewater.
Insert the other end of the strap into the mouth of plastic/glass container of limewater. The mouth of the straw should be submerged under the limewater. Secure the straw in place with modeling clay or play dough.
Leave the assembly undisturbed in a warm location for 24 hours. This condition will be called ‘+yeast’.
Repeat steps 1-8 but do not add the yeast. This condition will be called ‘-yeast’. Leave it undisturbed in a warm place for 24 hours.
After 24 hours, observe +yeast and –yeast and write down your observations.
•12 tall, slim glasses or clear plastic containers (water bottles are good)
•4 bendable straws
•4 straight straws (stirrers)
•Modeling clay or play dough
•Limewater
•1 box of glucose tablets (available at your local pharmacy; you need 6 5-gram tablets)
•Yeast (12 tablespoons total)
•Water
•White sugar
•Corn syrup
•Flour
•Vegetable oil
•Stove
•Over gloves
•Measuring cups and spoons
•Small pot
Experimental procedure
Make a 10% glucose solution by dissolving 6 5-gram glucose tablets in 300 ml of (about 1.25 cups). Gentle heating and stirring will help to dissolve the tablets. After the tablets are fully dissolved, boil the solution gently for five minutes to eliminate all oxygen in the glucose. Warning: be careful with hot stove, pot and liquid!!
Use oven gloves to remove the small pot of glucose from the stove. Allow it to cool (feels slightly warm to the touch).
Add 2 teaspoons of yeast to glass/plastic container. Pour the boiled glucose solution into the same container. Use a spoon/straw to gently mix.
Carefully pour half tablespoon of vegetable oil into the container so that it rests on top of the yeast- mixture to keep oxygen from entering the system.
Insert one bendable straw into the other bendable straw.
Bend the ends of both straws at a 90-degree angle. Place the end of one straw in the mouth in the plastic/glass container you just prepared. Secure it in place with modeling clay or play dough.
Fill a second plastic/glass container about three-fourths full of limewater.
Insert the other end of the strap into the mouth of plastic/glass container of limewater. The mouth of the straw should be submerged under the limewater. Secure the straw in place with modeling clay or play dough.
Leave the assembly undisturbed in a warm location for 24 hours. This condition will be called ‘+yeast’.
Repeat steps 1-8 but do not add the yeast. This condition will be called ‘-yeast’. Leave it undisturbed in a warm place for 24 hours.
After 24 hours, observe +yeast and –yeast and write down your observations.