Yeast bonghee2
Transcript of Yeast bonghee2
Name:…………Bonghee Han………………….. Yeast Experiment
Science Lab Report Yeast Growth Experiments date20~22/OCT/2010 Group member Bonghee, Jaffer, Toby Bonghee Han Aim The purpose of yeast growth experiment is to know basic knowledge of cell respiration by changing some variable.
Hypothesis Before starting experiments prediction was by changing amount of sugar the carbon dioxide will increase or decrease in direct proportionally. When the amount of sugar is increase the carbon dioxide also increase. When amount of sugar decrease carbon dioxide is decrease.
Variable Input variable Amount of sugar: 5g, 10g, 15g of sugar Sugar will be measured by electric weight without napkin.
Output variable Gas collection: How much ml of gas collection is moved Stop watch: Measure time for 10mins and for each min record
Control variable
#1 100ml of water for each experiment At the beaker there is the line to give information #2 Same size of beaker which is 200ml At the experiment beaker will be same #3 Same amount of yeast that is 5g Use electric weight to measure #4 Same size of gas collection which is 100ml Same types of gas collection #5 Same degree of water temperature There is machine to keep the water temperature same
Equipment
• 45g of yeast • 90g of sugar • One 200ml flask • One 100ml of gas collection • 300ml of water • One cork • One electric weight • Water bath
Diagram
Method
1. Set up the equipment as shown as Diagram 2. Ready 5g of yeast for each experiment 3. Ready 5g of sugar for each experiment 4. Put 100ml of water into 200ml of flask 5. Put sugar and yeast 6. Start stop watch 7. Take note for each min until 10mins 8. Clean the 200ml of flask 9. Repeat steps 2 to 8 using masses of 10g, 15g 10. Clean all the equipments
Data Table 1: Amount of sugar verses the amount of CO2 produced
ml
5g of sugar 10g of sugar 15g of sugar
Trial
B F B F B F
Trial 1 5 76 3 18.5 0.5 24.5
Trial 2 2 17 3 29 3.5 27
Trial 3 3 27.5 2 75 1 63
B‐Beginning F‐Final
Table 2: Amount of sugar verses the amount of CO2 produced
<Average> Trial ml 5g 10g 15g
Trial 1 71 15.5 24 Trial 2 15 26 23.5 Trial 3 24.5 73 62 Average 36.8 38.2 36.5 Graph
Conclusion According to the experiments data. There is no pattern for the data table 1 because for first trial 5g was the most improvement and for second trial 10g were the most improvement and the third trial 15g was the best. But when it turns to average there is pattern. If the human body consumes less sugar it produce high CO2. When human body consumes as many as body did it produce less CO2. The hypothesis was not reliable because it was when sugar increase body produces more CO2. The data is untrustworthy because it was all different result from same experiments.
Evaluation The method is trustworthy because it was the just listed basic ways. And there is repeating the process. Also method was ok but problem was the a bit different weight of sugar and the yeast. The three trials is completely error after experiment water for clean was not dried so yeast and sugar stick to top of flask. The error had huge effect to the experiment mixture of sugar and yeast were not completely mixed. The method should have more pacific of variable to do not change the result in same method of experiments.
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Trial 1 Trial 2 Trial 3 Averge
Gas(ml)
Trial
Yeast growth 5g
10g
15g