1. Empowering

2. • Carry out an experiment by using carbon dioxide
sensor to detect the carbon dioxide release by
yeast during fermentation.
• Different concentration of glucose is used to
observed the different in carbon dioxide
concentration collected.
• Data logger will collect time data and plot a
graph

3. Data and Analysis

4. Carbon dioxide concentration /ppm
Time/s

5. Discussion
1. Based on the table, we can observe that the
concentration of carbon dioxide increase from
time to time, what leads to this increment?
The changes of carbon dioxide level indicated
that the fermentation of yeast in glucose has
begun because more and more carbon dioxide
is release.

6. 2. What is the difference of above respiration with
human respiration?
The release of carbon dioxide indicates that this
is an anaerobic respiration. On the other hand,
human respiration is an aerobic respiration. The
main differences in anaerobic and aerobic
respiration is oxygen is absent in anaerobic
respiration while oxygen is present in aerobic
respiration. Oxidation of glucose is not complete
in anaerobic respiration but it is complete in
aerobic respiration.

7. 3. What are the similarities of above respiration to
human respiration?
Both of the respirations are cellular respiration
which involved the breakdown of glucose to
release energy that stores in ATP molecules.
4. Why paraffin oil is added to cover the glucose
solution?
Paraffin oil is added to prevent air from
dissolving in the glucose solution which might
affect the result.

8. 5. What is the function of pressure valve in the
experiment?
The valve is close to prevent air from
atmosphere to enter the conical flask which we
are monitoring the carbon dioxide release by
fermentation of yeast.
6. Write an equation for the above experiment.
C6H12O6 + 2 C3H5OH 2CO2 + 210 KJ
Glucose Ethanol Carbon dioxide Energy

9. 7. Calculate the rate of respiration of each
concentration of glucose. Which concentration
has the higher respiration rate?
rate of respiration for 10% glucose =
= 35.45 ppm/min
rate of respiration for 5% glucose =
= 114.22 ppm/min
Based on the calculation, we can observe that
5% glucose has the higher rate of respiration.
Calculation we obtained match the graph that
we plotted before.