Glycolysis and Fermentation A.K.A The Dough Lab

Pre-Lab Questions Answer these questions together as a group while you are in between measurements. What is the first step in the process of harvesting energy available in glucose? What are the energy requirements for glycolysis? In what conditions will anaerobic fermentation occur?

Experimental Question At which temperature will my dough rise the highest?

Brief overview of lab You will place bread dough in 3 different environments (cold, room temperature and warm). You will record their height every 5 minutes for 30 minutes.

Experimental Design What is the control group? The dough at room temperature What is the independent variable (X axis)? Time What is the dependent variable (Y axis)? Height of dough

Claim Statement I claim that my dough will rise the highest in a __________________ environment. cold room temperature warm

Evidence Data table: Under temperature, write cold, room temperature, and warm. You do not need the bottom column. Record your data here and exchange information with your group to have a complete data table. Put zero’s in under 0 min for the three temperatures. Graph: Line graph. Three lines, fill in the key (the three temperature environments) you can cross off the 4th Celsius. Each line should be a different color. Be sure to include labels and units.

Conclusion Questions Answer the 6 conclusion questions using your class notes and your data from the lab. You can work on these during the lab, in between readings.

Procedure 1. Label your test tubes C, R and W with a sharpie. Break off a pea size piece of dough and roll it into a skinny cylinder shape. It should be much skinnier than your test tube. Drop it into your test tube, it should hit the bottom. Use a pencil to push the dough into the bottom of the test tube. Be careful not to break the test tube. The dough should only fill about ¼ of the test tube. Repeat this step for the other 2 test tubes.

Mark the starting level of the dough in each test tube (draw a line using your sharpie). Place test tube C in an ice bath. Place test tube W in the incubator. Place test tube R in an empty beaker. Make note of the time. Record in mm the total height the dough rises in each test tube every five minutes for a total of 30 minutes. Note: always record the height from the sharpie mark.

After the 30 minutes are over and all of your data is filled into the data table, throw your test tubes away. Return your beakers. Return your sharpie and pencil. Clean up your area. Exchange data with your group. You should have a complete data table.

Reasoning Restate your claim: This is worth a lot of points. Take it seriously and spend some time on it. Ask me if you do not understand. Restate your claim: I claim that my dough will rise the highest in a __________________ environment. Discuss your data: Discuss the 3 different environments and how each affected the dough. Basically put your data table into sentences. Scientific Principle: Link this to an aspect in TODAY’S notes. What did you learn today and how did you demonstrate it in today’s lab?

Dough Recipe -yeast/sugar/water solution 500mL water + 30mL sugar + 10mL yeast Dough for students 100mL flour 50mL yeast solution 20mL sugar 20mL yeast (dry)