Name Date Period

Can You Spot The Scientific Method?

Each sentence below describes a step of the scientific method. Match each sentence with a step of the scientific method listed below.

A. recognize a problem C. test the hypothesis with an experiment

B.  form a hypothesis D. draw conclusions

_____ / 1. / Stephen predicted that seeds would start to grow faster if an electric current traveled through the soil in which they were planted.
_____ / 2. / Susan said, “If I fertilize my geranium plants, they will blossom.”
_____ / 3. / Jonathan’s data showed that household cockroaches moved away from raw cucumber slices.
_____ / 4. / Rene grew bacteria from the mouth on special plates in the laboratory. She placed drops of different mouthwashes on bacteria on each plate.
_____ / 5. / Kathy used a survey to determine how many of her classmates were left-handed and how many were right-handed.
_____ / 6. / Dana wanted to know how synthetic fibers were different from natural fibers.
_____ / 7. / Jose saw bats catching insects after dark. He asked, “How do bats find the insects in the dark?”
_____ / 8. / Arjulia soaked six different kinds of seeds in water for 24 hours. Then she planted the seeds in soil at a depth of 1 cm. She used the same amount of water, light, and heat for each kind of seed.
_____ / 9. / Bob read about growing plants in water. He wanted to know how plants could grow without soil.
_____ / 10. / Kevin said, “If I grow five seedlings in red light, I think the plants will grow faster than the five plants grown in white light.”
_____ / 11. / Angela’s experiment showed that earthworms move away from light.
_____ / 12. / May stated, “If acid rain affects plants in a particular lake, it might affect small animals, such as crayfish, that live in the same water.”
_____ / 13. / Michael fed different diets to three groups of guinea pigs. His experiment showed that guinea pigs need vitamin C and protein in their diets.
_____ / 14. / Kim’s experiment showed that chicken egg shells were stronger when she gave the hen feed to which extra calcium had been added.

Experimental Design Practice

15.  John’s parents would not let him study while listening to music in his room. They told him that he could not concentrate with the background noise. He decided to test this idea with an experiment on his class. Each Friday his English class took a vocabulary quiz on 25 new words learned that week. John got his teacher’s permission to try his experiment. On the first Friday of his test he played a rock song in the classroom while the class took the test. The following week the class took the test with the normal quiet atmosphere of a classroom. John calculated the average score on the two vocabulary tests. (Flip over to answer questions!)

a.  Independent Variable ______

b.  Dependent Variable ______

c.  Experimental Group ______

d.  Control Group ______

e.  Controlled Variables ______

16.  Use the line graph below to answer the following questions:

a.  Which plant grew the tallest? _____

b.  How many plants grew to be at least 6 cm tall? _____

c.  Which line represents plant 2? _____

d.  After 10 days, how much had plant 3 grown? ______

e.  What is the independent variable? ______

f.  What is the dependent variable? ______

17.  Scientists planted an equal number of plants in different soil temperatures. After 7 days, they counted the number of plants still alive. The following data was collected:

Effect of Soil Conditions on Plants

Light Exposure / Soil Temperature / # of Surviving Plants
Medium / 25°C / 10
Medium / 30°C / 6
Medium / 35°C / 2
Medium / 40°C / 1

a.  Independent Variable ______

b.  Dependent Variable ______

c.  Experimental Group ______

d.  Controlled Variables ______

e.  Possible Conclusion ______

f. Graph the date from the table above.