IS 119
607
Joe Bazooka
November 11, 2014
WITH
Peppermint Patty, Clark Kent and Betty Boop
TITLE
Mass of Plant Food vs. Average Height of Plant Growth
INTRODUCTION
Our problem asked whether increasing the amount of plant food would increase the height wheat grass would grow. Our
hypothesis stated that increasing the amount of plant food would increase the height of wheat grass. The data we
collected supported our hypothesis.
In the article, Plants Need Nutrition Too, I read that plants, like people, require food to grow.1 Like people, plants need
vitamins and minerals and many other nutrients. The data in our experiment supports this claim. However, in the
textbook selection, Fertilizers: Helping or Hurting, the authors suggest that too much plant food may not be a good for
plant growth.2 Our data does not support this claim.
In the future, we might expand the experiment to ask the question, can too much food effect the height plants will grow?
We could continue to increase the amount of plant food in order to determine whether too much plant food will cause a
decrease in the height that wheat grass grows.
VARIABLES
Independent Variable (IV) - mass of the plant food
Dependent Variable (DV) - average height of plant growth
Control Variables (CV) - amount of water and soil, height of the grow light, size of pots
PROBLEM
Will an increase the mass of plant food (IV) cause the increase in the height of wheat grass (DV)?
HYPOTHESIS
We think increasing the amount of plant food (IV) will result in an increase in the height of wheat grass (DV).
RATIONALE
Plants need food just like animals. Food helps things grow. It seems to make sense to me that the more food something
has the more it will grow.
MATERIALS
1. pots
2. seeds
3. plant food
4. water
5. soil
6. grow light
7. graduated cylinder
8. triple beam balance
9. metric ruler
PROCEDURES
Step 1: Label 3 pots Plants A1, A2 and A3, three pots Plants B1, B2 and B3, three pots Plants C1, C2 and C3.
Step 2: Measure 500 grams of soil with a triple beam balance and put it in each pot. (CV)
Step 3: Measure a hole 1centimeter deep in each pot using a ruler and place one seed in the hole. (CV)
Step 4: Measure 10 g of food with a balance and give to the first three pots labeled A1, A2 and A3. (IV)
Step 5: Measure 20 grams of food with a triple beam balance and give to Plants B1, B2 and B3. (IV)
Step 6: Measure 30 grams of food with a triple beam balance and give to Plants C1, C2 and C3. (IV)
Step 7: Place all plants 100 centimeters under the light. (CV)
Step 8: Measure the height of the plants in centimeters with a ruler after three months. (DV)
Step 9: Calculate the average height for Plants A1 to A3 using the formula: AHA= A1 + A2 + A3/ 3. Repeat for plants B
and C. (D.V.)
DATA TABLES
PLANTS A
PLANTS B
PLANTS C
Mass of Food (IV)
10 g
20 g
30 g
Trial 1
16 cm
23 cm
34 cm
Trial 2
18 cm
25 cm
32 cm
Trial 3
15 cm
24 cm
32 cm
Average Height AH
of Plant Growth (DV)
16.3 cm
24 cm
32.7 cm
DATA ANALYSIS
PLANTS A (10 grams of food)
PLANTS B (20 grams of food)
PLANTS C (30 grams of food)
AHA = (T1 + T2 + T3) / 3
AHB = (T1 + T2 + T3) / 3
AHC = (T1 + T2 + T3) / 3
AHA = (16 cm + 18 cm + 15 cm) /3
AHB = (23 cm + 25 cm + 24 cm) /3
AHC = (34 cm + 32 cm + 32) cm/3
AHA = 16.3 cm
AHB = 24 cm
AHC = 32.7 cm
AH = Average Height
DATA GRAPH
MASS OF PLANT FOOD VS. AVERAGE HEIGHT OF PLANTS
AVERAGE HEIGHT IN CMS (DV)
35
30
C
25
B
20
15
A
10
5
0
0
5
10
15
20
25
MASS OF PLANT FOOD IN GRAMS (IV)
30
35
CONCLUSION
Our hypothesis was supported by the data. We have concluded that an increase in the amount of plant food results in an
increase in the height of the plants. When the plants were given 10 grams of food, the average height of the plants was
16.3 cm. When the amount of plant food was increased to 20 grams, the average height of the plants increased to 24 cm.
When the plant food was increased to 30 grams, the average height increased to 32.7 cm.
REFERENCES
1. Science News Magazine, Plants Need Nutrition Too!, pp. 23 - 26
2. Science Textbook, Fertilizers: Helping or Hurting. p. 56
GLOSSARY
1. fertilizer - any substance placed in soil to help plants grow
2. nutrients - any substances that provides energy to a living organism helping it to survive and grow
3. minerals - substances found naturally in the earth, some of which are used by living things; like salt
APPENDIX
APPENDIX:
Plant A T1
10 grams of food
Plant A T2
10 grams of food
Plant A T3
10 grams of food
Plant B T1
20 grams of food
Plant B T2
20 grams of food
20 grams of food
Plant C T1
30 grams of food
Plant C T2
30 grams of food
Plant C T3
30 grams of food
Plant B T3