The affect of pH on Enzymes

Proposal Rubric
Purpose:
What would happen to a plant if the pH levels were different from the plants every day pH level? We now that the enzymes that allow photosynthesis and respiration to occur will work best in natural conditions. Will the enzymes adapt to the pH, or will the pH hinder the growth of the plant by denaturing the enzymes? In this experiment, my partner and I will be varying the pH level in different groups of plants to see how the enzymes will react to them by observing the growth rate of the plants.

Variables:
The independent variable will be the pH level of the water for each group of plants and the dependant variable will be the median of the height of the plants in each of the groups. Each group will have a pH level decreasing and increasing by an offset level of pH. The control would be the normal water used containing neither vinegar nor limestone.

If pH levels in the water, other than an enzymes natural level, denature an enzyme responsible for the growth of plants in height,
And we vary the level of pH,
Then the pH level closest to the plants natural level will allow the plant to have the most height.

Materials:
112 radish seeds
112 staples
14 plastic bags (recommended at least 8 by 8 inches)
14 paper towels
7 containers to hold solutions
graduated cylinder
pH meter
limestone
vinegar
Recommended:
Masking tape
Marker or Pen

Procedure:
1. Create a data chart similar to the one below including all the days between 3 and 30:
****************************************************************
Bag pH level Day 1 Day 2 Days 3 - 30 Day 31
****************************************************************
Amount of
water added N/A
1 (acidic) ---------- >
2
3 ---------- >
4 (water pH)
5 ---------- >
6
7 (alkaline) ---------- >
*****************************************************************
2. Be sure that the data chart is large enough, if needed use an excel spread sheet.
3. Put one paper towel into each of the 14 plastic bags; the bags should be at least 8 by 8 inches.
4. Label the bags 1 through 7 as follows: bag 1 would be labeled as "level: 1, Group 1", bag 2 would be "level: 2, Group 1", etc, bag 7 would be "level: 7, group 2".
5. Label the bags 8 through 14 as follows: bag 8 would be labeled as "level: 1, Group 2", bag 9 would be "level: 2, Group 2", etc, bag 14 would be "level: 7, group 2".
6. Staple 8 staples, distributed evenly, 1 inch from the bottom of each plastic bag.
7. Place 8 presoaked radish seeds on top of the stables in each of the 12 plastic bags.

8. Pour about 50 mL of water (either tap water or distilled water) into a container.
9. Using a pH meter, record the pH of the water into your data chart in the "level 4" row.
10. Add the water to both bags labeled "level 4" until the paper towel becomes moistened around all of the seeds. Record the amount of water used into day 1 of the data table.

11. Pour about 50 mL of water (the same kind of water used in step 8) into a container. (if using the same container of above, add the water needed to fill the container to 50mL)
12. Using a pH meter, add vinegar to the solution while stirring until the pH meter reads 1 level of pH lower then it did for the water used in step 8.
13. Record the pH level of the solution into your data chart in the "level 3" row.
14. Add the same amount of solution as you did in step 10 to both bags labeled "level 3" making sure to moisten the same area around the seed.

15. Pour about 50 mL of water (the same kind of water used in step 8) into a container. (if using the same container of above, add the water needed to fill the container to 50mL)
16. Using a pH meter, add vinegar to the solution while stirring until the pH meter reads 2 level of pH lower then it did for the water used in step 8.
17. Record the pH level of the solution into your data chart in the "level 2" row.
18. Add the same amount of solution as you did in step 10 to both bags labeled "level 2" making sure to moisten the same area around the seed.

19. Pour about 50 mL of water (the same kind of water used in step 8) into a container. (if using the same container of above, add the water needed to fill the container to 50mL)
20. Using a pH meter, add vinegar to the solution while stirring until the pH meter reads 3 level of pH lower then it did for the water used in step 8.
21. Record the pH level of the solution into your data chart in the "level 1" row.
22. Add the same amount of solution as you did in step 10 to both bags labeled "level 1" making sure to moisten the same area around the seed.

23. Pour about 50 mL of water (the same kind of water used in step 8) into a container. (Do not use the same container above unless the container has been washed out)
24. Using a pH meter, add limestone to the solution while stirring until the pH meter reads 1 level of pH higher then it did for the water used in step 8.
25. Record the pH level of the solution into your data chart in the "level 5" row.
26. Add the same amount of solution as you did in step 10 to both bags labeled "level 5" making sure to moisten the same area around the seed.

27. Pour about 50 mL of water (the same kind of water used in step 8) into a container. (if using the same container of above, add the water needed to fill the container to 50mL)
28. Using a pH meter, add limestone to the solution while stirring until the pH meter reads 2 level of pH higher then it did for the water used in step 8.
29. Record the pH level of the solution into your data chart in the "level 6" row.
30. Add the same amount of solution as you did in step 10 to both bags labeled "level 6" making sure to moisten the same area around the seed.

31. Pour about 50 mL of water (the same kind of water used in step 8) into a container. (if using the same container of above, add the water needed to fill the container to 50mL)
32. Using a pH meter, add limestone to the solution while stirring until the pH meter reads 3 level of pH higher then it did for the water used in step 8.
33. Record the pH level of the solution into your data chart in the "level 7" row.
34. Add the same amount of solution as you did in step 10 to both bags labeled "level 7" making sure to moisten the same area around the seed.

35. Tape each of the plastic bags to a window (or other light source)
36. Everyday for the next 31 days, record the height of each of the seeds into the proper day from each bag using centimeters as the base unit. (combine both groups, 1 & 2, into the same space)
37. Everyday for the next 31 days, check to see if any of the bags require more water, if so add the correct pH level of water to all the bags adding the same amount of water to each bag. Record the amount of water added into the data table.
38. (Optional to add more control to the experiment) Rotate the position of the bags daily to ensure each bag receives equal amount of sunlight.
39. (Optional to add more control to the experiment) Maintain the same containers each filled with solution for the entire time period. Keep the water so you don't have to keep making it every time you wish to water the plants. Keep in sealed container and periodically check the pH levels to ensure that they haven't changed. You may also need to have more than the initial 50 mL.

Data Interpretation:
In the end 31 bar graphs and 31 box-plots will be produced comparing the height of each plant each day. Along with the graphs will be a chart comparing the height of each plant for each day. We will be able to see the amount the groups grew in height for each of the days tested compared against each other. If the plants with the pH level closest to the natural level of the radish plants have the most gain in height, and the other radish plants decreasing in height as the pH moves farther away from the natural pH of the radish plant, then it shows that enzymes were denatured by the difference in pH. However, if there is no major change in height between the pH closest to the natural level of radish plants to the remaining pH levels, then the enzymes were not denatured.

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