Name: ____________________________________
Block: ________
Scientific Method – Review Sheet
1. LIST the steps of the scientific method and DEFINE each step.
2. What is the difference between a control and a variable?
3. What are the THREE ways to draw conclusions?
4. Define THREE terms you wrote in number 3.
5. A student investigated the effect of radiation on the germination of bean seeds. He
thought that exposure to radiation would limit the seeds ability to germinate (grow) much
like ultra- violet light causing skin cancer. Three hundred seeds were soaked in distilled
water for one hour. They were then divided into three groups. One group was placed in a
microwave oven on high for three seconds. Another group was microwaved on high for six
seconds. The last group was not microwaved. The seeds were then planted in three
separate flats and given the same amount of water. The seeds were then planted in three
separate flats and given the same amount of water. The flats were placed in a location with
a constant temperature of approximately 27 degrees Celsius. Each day for two weeks the
number of seeds that germinated each group was recorded.
Total Number of Bean Seeds Germinated after Microwave Radiation
Three Seconds of Radiation Six Seconds of Radiation No Radiation 54 26 88
No Radiation
88
3 Seconds of Radiation
54
6 Seconds of Radiation
26
a) Which is the control group? ________________________________________________
b) Which is/are the experimental (variable) group(s)? ________________________________________
c) What is the Independent Variable? ___________________________________________
d) What is the Dependent Variable? ___________________________________________
e) Is a “good” experiment? Why or why not?
f) What (if anything) can be concluded about the effect of radiation on bean plant
germination?
6. Maggie read that some plants grow better if the soil is acidic. She can’t believe that a
plant can grow when exposed to acid! Maggie decides to test if the plants she has will grow
better when acid is added to the soil. She puts potting soil in two planting containers and
transplants two of her geraniums that seem about the same size into the pots. She puts the
pots in the same location so that they both get the same sunlight each day, are at the same
temperature and she makes sure they get the same amount of water. However, Maggie puts
a tablespoon of vinegar in the water she gives to one of the plants and 2 tablespoons of
vinegar in the water she gives to the other plant. She measures the growth of the plants
every week for four weeks and records the results in a data table below:
Week
1
2
3
4
Height of Plant in Container
with 1 Tablespoon of
Vinegar (cm)
10.0
12.4
15.1
17.8
a) What is the control? ________________________________________________
b) What is the variable? ________________________________________
c) Is this a “good” experiment? Why or Why not?
Height of Plant in Container
with 2 Tablespoons of
Vinegar (cm)
10.1
16.7
19.0
22.3