Experiment
1: I Put My Hand On That Every Day?!?!
Experiment 2:That's From My Keyboard?!?!
Experiment 3: I Talk On That Thing?!?!
Experiment 1 Results
Experiment 2 Results
Experiment 3 Results
Pictures of us doing
our experiment
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Experiment 1: I Put My Hands On That Every Day?!?!
Problem: Does the Amount of time
that a sample of doorknob bacteria is exposed to ultrasonic waves have an
effect of the growth of the bacteria.
Materials:
12 Petri Dishes (with agar)
12 Samples of Doorknob Bacteria
Ultrasound machines (all set with the same
amount of output power [12 MHz])
Variables:
Manipulated: Amount of Time Bacteria
is Exposed to Ultrasound Waves
Responding: Amount of Growth of Bacteria
Procedure:
1) Get 12 samples of bacteria from doorknob,
using Q-tips, all from same doorknob.
2) Rub bacteria onto the center of the
dishes. The same amount of bacteria on each. (This is the formation that we
applied the bacteria with: (Note: the rectangle is filled in with bacteria)
Fig. 31: Application of Bacteria
This is the above formation, only we have
broken down the steps for you.
Fig. 32: Application of Bacteria
Fig. 33: Application of Bacteria
Fig. 31: Application of Bacteria
3) Tape up and label all samples.
Fig. 46: 2 hr petri
dishes
4) Put all samples in controlled environment
(dark room, room temperature)
5) Leave dishes in controlled climate for
8 days
6) On 8th day, take out of room, measure
amount of bacteria growth using ruler. Measure surface area (just 2D, only
on top). Record quantitative observations.
Fig. 47:Measuring
7) Keep 3 samples in dark room for next
4 steps as controls
8) Invert dish and apply ultrasound gel
to the probe.
Fig. 48: Ultrasounding
9) Ultrasound 3 dishes for ½ hour.
Make sure to keep power level the same.
10) Ultrasound 3 dishes for 1 hours. Make
sure to keep power level the same.
11) Ultrasound 3 dishes for 2 hours. Make
sure to keep power level the same.
12) Put 9 ultrasounded dishes back in controlled
environment with the 3 controls.
14) Take out all 12 samples of environment.
15) Measure surface area of all 12 samples.
Record quantitative observations.
16) Compare results and find percentage
of bacterial growth or decrease.
17) Return all 12 samples back to controlled
environment and keep them there for 7 days from the day of ultrasounding
18) Compare results and find percentage
of bacterial growth or decrease.
19) Safely discard all petri dishes
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Experiment 2:
That's from our Keyboard?
Problem: Does the Amount of time
that a sample of computer keyboard bacteria is exposed to ultrasonic waves
have an effect of the growth of the bacteria.
Materials:
12 Petri Dishes (with agar)
12 Samples of Computer Keyboard Bacteria
Ultrasound machines (all set with the same
amount of output power [12 MHz])
Variables:
Manipulated: Amount of Time Bacteria
is Exposed to Ultrasound Waves
Responding: Amount of Growth of Bacteria
Procedure:
1) Get 12 samples of bacteria from Computer
Keyboard, using Q-tips, all from same keyboard.
2) Rub bacteria onto the center of the
dishes. The same amount of bacteria on each. (This is the formation that we
applied the bacteria with: (Note: the rectangle is filled in with bacteria)
Fig. 31: Application of Bacteria
This is the above formation, only we have
broken down the steps for you.
Fig. 32: Application of Bacteria
Fig. 33: Application of Bacteria
Fig. 31: Application of Bacteria
3) Tape up and label all samples.
Fig. 46: 2 hr petri dishes
4) Put all samples in controlled environment
(dark room, room temperature)
5) Leave dishes in controlled climate for
8 days
6) On 8th day, take out of room, measure
amount of bacteria growth using ruler. Measure surface area (just 2D, only
on top). Record quantitative observations.
Fig. 47:Measuring
7) Keep 3 samples in dark room for next
4 steps as controls
8) Invert dish and apply ultrasound gel
to the probe.
Fig. 48: Ultrasounding
9) Ultrasound 3 dishes for ½ hour.
Make sure to keep power level the same.
10) Ultrasound 3 dishes for 1 hours. Make
sure to keep power level the same.
11) Ultrasound 3 dishes for 2 hours. Make
sure to keep power level the same.
12) Put 9 ultrasounded dishes back in controlled
environment with the 3 controls.
14) Take out all 12 samples of environment.
15) Measure surface area of all 12 samples.
Record quantitative observations.
16) Compare results and find percentage
of bacterial growth or decrease.
17) Return all 12 samples back to controlled
environment and keep them there for 7 days from the day of ultrasounding
18) Compare results and find percentage
of bacterial growth or decrease.
19) Safely discard all petri dishes
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Experiment 3: I Talk on That Thing?
Problem: Does the Amount of time
that a sample of telephone keypad and microphone bacteria is exposed to ultrasonic
waves have an effect of the growth of the bacteria.
Materials:
12 Petri Dishes (with agar)
12 Samples of Telephone Keypad and Microphone
Ultrasound machines (all set with the same
amount of output power [12 MHz])
Variables:
Manipulated: Amount of Time Bacteria
is Exposed to Ultrasound Waves
Responding: Amount of Growth of Bacteria
Procedure:
1) Get 12 samples of bacteria from telephone
keypad and microphone, using Q-tips, all from same telephone.
2) Rub bacteria onto the center of the
dishes. The same amount of bacteria on each. (This is the formation that we
applied the bacteria with: (Note: the rectangle is filled in with bacteria)
Fig. 31: Application of Bacteria
This is the above formation, only we have
broken down the steps for you.
Fig. 32: Application of Bacteria
Fig. 33: Application of Bacteria
Fig. 31: Application of Bacteria
3) Tape up and label all samples.
Fig. 46: 2 hr petri dishes
4) Put all samples in controlled environment
(dark room, room temperature)
5) Leave dishes in controlled climate for
8 days
6) On 8th day, take out of room, measure
amount of bacteria growth using ruler. Measure surface area (just 2D, only
on top). Record quantitative observations.
Fig. 47:Measuring
7) Keep 3 samples in dark room for next
4 steps as controls
8) Invert dish and apply ultrasound gel
to the probe.
Fig. 48: Ultrasounding
9) Ultrasound 3 dishes for ½ hour.
Make sure to keep power level the same.
10) Ultrasound 3 dishes for 1 hours. Make
sure to keep power level the same.
11) Ultrasound 3 dishes for 2 hours. Make
sure to keep power level the same.
12) Put 9 ultrasounded dishes back in controlled
environment with the 3 controls.
14) Take out all 12 samples of environment.
15) Measure surface area of all 12 samples.
Record quantitative observations.
16) Compare results and find percentage
of bacterial growth or decrease.
17) Return all 12 samples back to controlled
environment and keep them there for 7 days from the date of ultrasounding
18) Compare results and find percentage
of bacterial growth or decrease.
19) Safely discard all petri dishes
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EXPERIMENT 1: DOORKNOB
BACTERIA
| Dish Number (Hours Exposed) |
1 (0) |
2 (0) |
3 (0) |
4 (1/2) |
5 (1/2) |
6 (1/2) |
7 (1) |
8 (1) |
9 (1) |
10 (2) |
11 (2) |
12 (2) |
| Surface Area - Day of Ultasounding (cm³) |
0.6 |
0.04 |
0.04 |
5.30 |
0.54 |
11.25 |
4.93 |
4.95 |
3.10 |
1.35 |
0.41 |
0.39 |
| Surface Area - 2 Days After Ultrasounding (cm³) |
1.30 |
0.30 |
0.85 |
6.75 |
1.28 |
9.32 |
6.79 |
4.32 |
4.87 |
2.27 |
0.62 |
0.54 |
| Percentage of Bacteria Growth or Loss |
117% |
650% |
1985% |
27% |
137% |
-17% |
38% |
-13% |
57% |
68% |
51% |
38% |
| Average Growth of Group |
0 Hours: 1579% |
1/2 Hour: 49% |
1 Hour: 27% |
2 Hours: 52% |
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EXPERIMENT 2: KEYBOARD BACTERIA
| Dish Number (Hours Exposed) |
1 (0) |
2 (0) |
3 (0) |
4 (1/2) |
5 (1/2) |
6 (1/2) |
7 (1) |
8 (1) |
9 (1) |
10 (2) |
11 (2) |
12 (2) |
| Surface Area - Day of Ultasounding (cm³) |
1.84 |
8.31 |
3.93 |
5.25 |
11.94 |
11.16 |
6.68 |
7.36 |
8.86 |
7.28 |
10.32 |
11.30 |
| Surface Area - 2 Days After Ultrasounding (cm³) |
3.96 |
9.75 |
6.10 |
5.12 |
13.5 |
10.64 |
7.44 |
5.67 |
9.40 |
7.51 |
10.67 |
10.16 |
| Percentage of Bacteria Growth or Loss |
115% |
17% |
55% |
-2% |
13% |
-4% |
11% |
-22% |
6% |
3% |
3% |
-10% |
| Average Growth of Group |
0 Hours: 62% |
1/2 Hour: 2% |
1 Hour: -1% |
2 Hours: -1% |
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EXPERIMENT 3: TELEPHONE BACTERIA
| Dish Number (Hours Exposed) |
1 (0) |
2 (0) |
3 (0) |
4 (1/2) |
5 (1/2) |
6 (1/2) |
7 (1) |
8 (1) |
9 (1) |
10 (2) |
11 (2) |
12 (2) |
| Surface Area - Day of Ultasounding (cm³) |
6.16 |
3.84 |
1.02 |
0.98 |
1.74 |
0.25 |
3.07 |
0.54 |
0.71 |
0.88 |
4.56 |
2.10 |
| Surface Area - 2 Days After Ultrasounding (cm³) |
7.97 |
6.20 |
1.19 |
1.10 |
2.37 |
1.47 |
2.94 |
1.27 |
1.42 |
0.75 |
3.21 |
1.92 |
| Percentage of Bacteria Growth or Loss |
30% |
61% |
17% |
12% |
36% |
488% |
-5% |
122% |
97% |
-15% |
-136% |
-9% |
| Average Growth of Group |
0 Hours: 36% |
1/2 Hour: 178% |
1 Hour: 71% |
2 Hours: -53% |
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