Experiments
Procedure & Results
Protocol
Mealworm Dissection
LB Agar Medium Synthesis
Materials Needed:
Water(purified water)
LB broth (salt, yeast, 카세린), since we’re making a 500ml solution, we’ll need 12.5g
25g/liter
AGAR (not easily disintegrated by bacteria, structure preserved)
Has to be 1.5% of the solution
Since we’re making a 500ml solution, we’ll need 7.5g
Autoclave
High pressure, high temp sterilization
More than 20 minutes
Procedure:
1. Put water up to 500ml in a graduated cylinder pour it in a large flask
2. Measure LB broth carefully to match 12.5g inside the a plastic temporary container
3. Close the lid to the LB broth, wash the spoon used to transfer it
4. Fold the plastic container in half and pour the LB broth into the flask
5. In the same manner, put AGAR(7.5g) inside the flask
6. Don’t mix he flask, and seal the top of the flask with a tin foil
7. Put it in the autoclave, pour some hot water and close the lid wait for an hour and half
8. When storing the AGAR medium, make sure to preserve it in 60 degree cel.
9. Go to the clean bench, or if it’s unavailable you kindle the alcohol lamp
->(which causes convection and so in a sense forms an umbrella that protects the plate from contamination from the air)
10. Pour the AGAR solution onto eight plates, making sure your hand or your other body part is not hovering over the plate
->(you always have to keep in mind that SOMETHING’s falling from the air.
11. Close the lids of the all eight plates and wait till they harden.
Chemical Transformation
Basic Knowledge:
Competent cell
e-coli’s name : DH5-alpha
DNA to be Added : PUC19
Procedure:
1. Prepare two containers
only the DH5-alpha
DH5 alpha + PUC19 (experimental group)
Put both containers in ice for a minute
2. Raise the temperature abruptly to 42 degrees Cel for a minute
3. Put them into ice for another 2 minutes
4. At the Clean Bench, put LB Medium equally to each container
5. 37°C 180 RPM (at least 30-min)
6. In the centrifuge, 30 seconds at highest speed
7. With a Pipet eliminate remaining precipitate
8. In the LB Medium plate, put appropriate number of glass beads
9. After mixing the substances in the two containers with the pipet,
10. Put the two substances into each separate LB plates, put the lid on top and shake
11. Seal the plate
12. Wait for 2 days until results show up
Experiment
1. Confirming that indeed these mealworms digest plastic and recording how much they eat in a day
Data Table
Experiment1: Influence of light on mealworms
Initial condition | ||||||||
1. Meal worms are in transparent container of its area of base (20X13)cm^2 | ||||||||
2. Meal worms' size in average was (2X0.2)cm^2 | ||||||||
3. Experiment period : 5/20(Fri)~7/01 (measured every Friday) | ||||||||
4. Meal worms are eating only polystyrene(4.00g) | ||||||||
5. One container is put in shade, another in light | ||||||||
Experiment Result | ||||||||
Date | Shade/Light | |||||||
Population [meal worm larva] | ||||||||
number of imago | ||||||||
5/20 | 5/27 | 6/3 | 6/10 | 6/17 | 6/24 | 7/1 | ||
I-A | light | 30 | 30 | 30 | 30 | 30 | 30 | 30 |
0 | 0 | 0 | 1 | 3 | 3 | 4 | ||
I-B | shade | 30 | 30 | 30 | 30 | 30 | 30 | 30 |
0 | 0 | 0 | 0 | 0 | 0 | 1 |
Conclusion
1. Meal worms become imagos faster in light than in shade |
Initial condition | ||||||
1. Meal worms are in transparent container | ||||||
2. Meal worms's size in average was (2.6X0.4)cm^2 | ||||||
3. Experiment period : 7/01(Fri)~ (measured once in two weeks) | ||||||
4. Meal worms are put in shade | ||||||
5. Meal worms are eating only polystyrene | ||||||
Experiment Result | ||||||
Date | 7/10 | 7/15 | 7/29 | 8/12 | 8/26 | |
Meal worm | 108 | 102 | 92 | 86 | 76 | |
Imago(alive+dead) | 5 | 11 | 19 | 25 | 32 | |
Dead meal worm | 0 | 0 | 2 | 2 | 5 | |
Dead Imago | 0 | 0 | 2 | 19 | 32 | |
TOTAL | 113 | 113 | 113 | 113 | 113 |
Conclusion
1. Imago cannot survive depending only on polystyrene | ||||||
2. Imagos reproduced, and we could find about 40 larvas that were newly born (there may be more since we couldn't separate the larvas of less than 7mm from excreta) |
||||||
3. newly born larvas were gathered and grown in another transparent container in sawdust |
Experiment3: Decomposition Rate of Polystyrene by Mealworms
Initial condition | |||||||||||||||||||
1. Group A and B each has 10 meal worms in their container | |||||||||||||||||||
2. Meal worms in Group A, B are fed only on polystyrene | |||||||||||||||||||
3. Group C has only polystyrene in its container | |||||||||||||||||||
4. Group A and C experiment started in 8/24 | |||||||||||||||||||
5. Group B experiment started in 8/25 | |||||||||||||||||||
6. Meal worms are put in shade | |||||||||||||||||||
Experiment Result | |||||||||||||||||||
Date | 8/24 | 8/25 | 8/26 | 8/27 | 8/28 | 8/29 | 8/30 | 8/31 | 9/1 | 9/2 | 9/3 | 9/4 | 9/5 | 9/6 | 9/7 | 9/8 | |||
w_A(t) | 4.00 | 3.99 | 3.98 | 3.97 | 3.97 | 3.96 | 3.96 | 3.96 | 3.94 | 3.94 | 3.93 | 3.93 | |||||||
w_B(t) | 4.00 | 3.99 | 3.98 | 3.97 | 3.97 | 3.96 | 3.96 | 3.95 | 3.95 | 3.94 | |||||||||
n_A(t) | 10 | 10 | 10 | 9 | 9 | 8 | 8 | 8 | 8 | 8 | 8 | 8 | |||||||
n_B(t) | 10 | 10 | 10 | 10 | 10 | 9 | 9 | 9 | 9 | 9 | 8 | 8 | 8 | 8 | |||||
Date | 9/9 | 9/10 | 9/11 | 9/12 | 9/13 | 9/14 | 9/15 | 9/16 | 9/17 | 9/18 | 9/19 | 9/20 | 9/21 | 9/22 | 9/23 | ||||
w_A(t) | 3.92 | 3.91 | 3.91 | 3.91 | 3.91 | 3.90 | 3.90 | 3.90 | 3.89 | 3.89 | 3.89 | ||||||||
w_B(t) | 3.93 | 3.92 | 3.91 | 3.91 | 3.91 | 3.90 | 3.90 | 3.90 | 3.89 | 3.89 | 3.89 | ||||||||
n_A(t) | 7 | 7 | 6 | 6 | 6 | 6 | 6 | 5 | 5 | 5 | 5 | ||||||||
n_B(t) | 8 | 8 | 7 | 7 | 7 | 7 | 6 | 6 | 6 | 6 | 6 |
After feeding 40 mealworms with only plastic for 5 weeks, we measured the length and the weight of the 20 samples. The average weight is 0.177g per worm and the original length is about 3+- 0.4cm. Compared to the original length 2+-0.2cm, it is noticeable that mealworms are possible to continue their lives with plastics as their only source of nutrient.
Conclusion
1. The average decomposition rate of polystyrene by mealworms was 4.720939905382693E-4g of polystyrene a day. | ||||||
2. Such decomposition rate can be drew by the formula |