8 Carolina Distance Learning
ACTIVITY

A Fermentation of Monosaccharides and Disaccharides
1. With a grease pencil, label one bottle
“Glucose,” one “Sucrose,” and one
“Lactose.”
2. Weigh 1 gram of sucrose in a weigh boat on
the balance.
3. Add the sugar to the “Sucrose” bottle. Repeat
weighing for the two other sugars.
4. Turn on a hot water tap and monitor the
temperature with a thermometer until a 35 °C
is achieved. Collect approximately 125 mL of
35 °C water in the beaker.
5. Weigh 2 grams of yeast, and add it to the 35 °
C water in the beaker. Stir thoroughly with the
spoon.
6. With a 10-mL graduated cylinder, add 6 mL
yeast solution to each small bottle.
7. Layer approximately ½ cm of baby oil on top
of the yeast solution in each bottle. Be careful
not to mix the oil with the solution below.
8. Insert the bottle dropper tops on the bottles.
9. Turn on a hot water tap and monitor the
Figure 1. temperature with a thermometer until a 35 °C is achieved. Fill three foam cups with 35 °C
water.
10. Fill three 15-mL centrifuge tubes with 35 °C water.
11. Insert a piece of tubing into each of the centrifuge tubes, bend the tubing, and place a finger on top of the centrifuge tube. Quickly invert the centrifuge tube and place it in the foam cup. Make sure as much water as possible stays in the centrifuge tube. The final
result should resemble Figure 1. Make sure the end of the tubing is above the water level; if not, the water will empty out of the tube. Setting up a Gas Collection
Apparatus https://players.brightcove.
net/17907428001/HJ2y9UNi_default/index. html?videoId=4573398321001 12. Fill three more foam cups with 35 °C water. 13. Attach the tubes to the bottle dropper tops as shown in Figure 1. Insert the sugar and yeast-filled bottles into the foam cups with 35 °C water. 14. Record the initial gas volume in each centrifuge tube in Data Table 1. continued on next page

mL CO2 /gram = (Start volume water tube – end volume water tube)
Grams of sugar 18. Divide the number obtained from Step 17 by 60 minutes or the time required to completely fill the tube. Record these values in Data Table 2. Note the differences between the sugars used.
19. Using the data from Step 18, calculate the amount of ATP produced. Divide the CO2 gas volume calculated in Step 18 by 24,000 mL/mole to get the moles of CO2 produced. The moles of CO2 produced are the same as the moles of ATP produced. Record these= numbers in Data Table 2.
20. Dismantle and clean the setup. The bottle contents can be disposed of in the sink with the faucet running. Rinse the tubes, bottles, and tubing.
ACTIVITY 2
A Fermentation of Polysaccharides
1. With a grease pencil, label one bottle “Sucrose,” one “Starch,” and one “Cellulose.”
2. Add 1 gram of sucrose to the Sucrose bottle, 1 gram of starch to the Starch bottle, and 1 gram of cellulose to the Cellulose bottle. Prepare the bottles as described in Activity 1, Steps 2–10.
3. Attach the tubing and complete the setup as described in Activity 1, Steps 11–13, shown in Figure 1. Make sure the water baths around the bottles are 35 °C.
4. Note the gas volumes in the centrifuge tubes and record them as the starting volumes in Data Table 3.
5. Monitor the water levels in the centrifuge tubes for 60 minutes. Record the water levels every 15 minutes in Data Table 3. Make sure the water in the foam cups stays close 6. After 60 minutes, calculate the total amount of gas produced for each bottle
per gram of sugar as described in Activity 1, Step 17. 7. Use the formula from Activity 1, Step 18, and calculate the moles of CO2 gas produced per minute for each tube. Record the values in Data Table 4.
8. Using the data from Step 7, calculate the amount of ATP produced. Divide the CO 2 gas volume calculated in Step 18 by produced. The moles of CO produced are2 the same as the moles of ATP produced. Insert these numbers in Data Table 4