Biology Sba Sample

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Biology Sba Sample

By | April 2012
Page 1 of 2
Plan and Design #
SBA #
Title: Conditions needed for dough to rise
Hypothesis: Conditions needed in order for dough to rise properly Aim: To determine what conditions make dough rises best
Apparatus and materials
Flour
Yeast
Warm water
Sugar
Mixing bowl
Two (2) beakers
Measuring cup
Spoon

Diagram of Apparatus

Method
1. Take a measuring and measure 1 and ½ cups of warm water 2. Add yeast then sugar (this is used to activate the yeast. The yeast uses the sugar and water to create carbon dioxide and raise the bread) 2. Add the yeast mixture to the mixing bowl along with ¾ of flour 3. Mix the ingredients with a wooden spoon

4. Begin to knead the dough until smooth
5. Take the dough and cut it into 2 equal sizes
6. Take both pieces of dough and place one in a dark cupboard and the other in the refrigerator. Leave dough for 1 day. (The oven and the refrigerator are both conditions to test what is best for bread to rise.) 8. Observe dough to see which one raised best

Expected results
The dough that is placed in the cupboard is more likely to give the best result. This is so because yeast works best in warm environments. The warmth enhances the yeast’s metabolism and causes it to work faster at raising the dough; one enzyme goes to work on the flour, changing the starch in it into sugar. Another enzyme then takes over and changes the sugar into alcohol and carbon dioxide. The refrigerated dough would have adverse effects because cold conditions slow down the yeast’s performance.

Experimental limitations/Sources of error
1. The temperature in the cupboard and refrigerator may be too high or too low to actually analyze the way dough raises. Conditions like a hot day or a rainy day would have been preferred. 2. Not kneading the dough properly

3. Using expired yeast
4. Excess addition of ingredients