Introduction to Biology

Lesson 3

100 Points

Name ______

Scientific Method Matching

Directions: Cut out the definitions on the next page that says “Scientific Method Definitions”. Match the appropriate definition with the scientific vocabulary term shown below. Pages 3 – 15 will help you.

Vocabulary Term / Definition
Scientific Method
Steps of the Scientific Method:

1. Problem
2. Research/Background Information
3. Hypothesis

4. Observation
5. Experiment
A. Independent Variable
B. Dependent Variable

C. Control
D. Constants
E. Repeated Trials
6. Data Collection and Analysis

7. Conclusion

CONTROLLED EXPERIMENTS

Directions: For each description, determine the following: hypothesis, independent variable, dependent variable, control, and any factors that would need to be constant.

1. A zoologist wants to know if feeding mice a vitamin supplement will make them grow larger. She feeds five mice their regular food, and she feeds five other mice food with vitamins. She measures the weight of the mice at the start and end of the experiment.

hypothesis: ______

independent variable: ______

dependent variable: ______

control: ______

constants: ______

2. A student is interested in the effect of the temperature of water in her aquarium on the activity level of her fish. She divides her aquarium water and fish into three aquariums, one that is maintained at room temperature (about 70F), one that is heated to 80F, and one that is cooled to 60F. At six p.m. each day, she watched the fish for 30 minutes and records her observation about their activity.

hypothesis: ______

independent variable: ______

dependent variable: ______

control: ______

constants: ______

4. The student described in # 3 is also curious about which kind of fish food will make her fish the most active. She decides to test fish food type in the experiment described above. Explain why this is not a good idea. ______

The Case of the Sleeping Frog

Directions: Read the following paragraphs that describe an investigation conducted by Kara, a bright science student. Put the paragraphs in the correct sequence by writing the appropriate number on the line provided and label them with the step of the scientific method they represent. You will use this information to answer the analysis questions based on Kara’s experiment. (14 points)

______Kara obtained two one-liter jars and placed a frog in each. She inserted a thermometer through a hole in the screened lid of each jar. She then placed each jar inside a larger jar. Kara filled one of the larger jars with ice cubes until the cubes surrounded the smaller jar that held the frog. Kara did not put any ice cubes in the other set of jars.
Step of scientific method ______
______Kara went to the library to read about hibernation. She read several articles on the topic.
Step of scientific method ______
______Kara, a curious frog loving science student, wanted to know how she could make a frog hibernate.
Step of scientific method ______
______Kara created a graph of the data to help her determine what had happened and why.
Step of scientific method ______
______Every 30 minutes, Kara recorded the temperature inside each of the two smaller jars. She also recorded the breathing rate of the frog and other observations about the frog’s appearance and behavior. Kara noted that in the jar with the ice cubes, the frog began to move more slowly and finally seemed to go to sleep. The frog’s rate of breathing became slower, too. These changes did not occur in the other jar. When the ice was removed from the first jar, the frog gradually became more active.
Step of scientific method ______
______After reading about the topic, Kara made an educated guess. She guessed that she could make a frog hibernate by making it cold.
Step of scientific method ______
______Kara came up with a summary of the results of her experiment.
Step of scientific method ______

Directions: Use the set of ordered squares to answer the following analysis questions related to Kara’s experiment

1.  What was Kara’s hypothesis? What clued you in that this was her hypothesis? (2pts) ______

2.  Here is a list of Kara’s materials, complete the diagrams below to show an example of the set up that Kara used for her experiment, including the thermometers, screened lids, small jars, large jars, frogs, and ice cubes. Be sure to label all parts on both pictures. (11 points)

Without Ice With Ice

a. List the materials that remained constant? (1 point)

______

b. Which material is the variable? (1 point)

______

c. Label the control group and the experimental group. (2 points)

4. A) What is the independent variable (1 pt) (what does Kara control in the experiment)? ______

B) What is the dependent variable (1 pt) (what depends on the independent variable)?

______

C) What jar serves as the control? Why? ______

5. Here is Kara’s data. Use graph paper to graph the temperature and breathing rate over time. You will have four lines (one for temperature Jar A, temperature Jar B, breathing rate jar A and breathing rate jar B). You must create a KEY. (10 points)

Time / Temperature / Breathing Rate / Activity Level
Jar A / Jar B / Jar A / Jar B / Jar A / Jar B
0 min / 22ºC / 22ºC / 29 / 30 / Normal / Normal
30 min / 22ºC / 20ºC / 30 / 26 / Normal / Normal
60 min / 22ºC / 15ºC / 31 / 21 / Normal / Slowing
90 min / 22ºC / 8ºC / 30 / 18 / Normal / Slow
120 min / 22ºC / 4ºC / 29 / 14 / Normal / Sleeping
150 min / 22ºC / 4ºC / 29 / 17 / Normal / Sleeping
180 min / 22ºC / 4ºC / 30 / 16 / Normal / Sleeping
210 min / 22ºC / 14ºC / 31 / 20 / Normal / Waking
240 min / 22ºC / 18ºC / 28 / 25 / Normal / Normal
270 min / 22ºC / 22ºC / 30 / 29 / Normal / Normal

6. Explain in complete sentences what Kara’s results show for:

Jar A: ______

Jar B: ______

7. Conclusions:

A. What was the problem Kara wanted to investigate? ______

B. Do her results support her hypothesis? Why or why not? ______

C. What conclusions can Kara draw from her experiment? Provide a biological explanation for her results (what happens when things get cold?) ______

An interpretation and summary of the results of an experiment based on the collected data / Using all the senses to study a problem
Accurate recording of data in an organized manner (may include tables, graphs, etc.) / The factor that responds or depends upon the independent variable (can be many)
A test for the hypothesis performed under controlled conditions / Performing the experiment numerous times or having many trials run simultaneously to verify results
Factors that remain the same during an experiment / The factor that is used as the standard to which everything is compared
A logical and organized way to solve a problem / A statement that can be tested as a possible explanation for a set of observations
Some questions about the world and the occurrences in it / Searching, collecting, and studying information from a variety of sources
The one and only factor that is changed or varied by the experimenter in an experiment

Lesson 3 Page 1