Using the Scientific Method

2002 and 2014 GED Content Area: Science Focus: Scientific Method (2002) and Scientific Hypothesis and Investigation(2014) Activity Type: Graphic Organizer and GED Practice

Objectives Students will be able to:  Appreciate the purpose of the Scientific Method  Understand key terms related to the Scientific Method: observation, hypothesis, test, experiment, result, conclusion  Relate the Scientific Method to an experiment  Answer GED questions based on the Scientific Method

Directions 1. Print the handout “Using the Scientific Method” (next page). Pass out the handout to the class. 2. Explain that the scientific method is the way scientists learn about the world around us. This involves several steps, often in the form of experiments. Discuss the 5 steps in the chart on the handout and define the highlighted words. 3. Have a student or students read the first passage out loud. Ask the class to fill in the chart. They can fill in the chart individually or in pairs (discussing these concepts can help students develop their thinking skills). 4. Discuss the students’ answers. Samples: 1. Observation: Where there was Penicillium mold, there were also dead bacteria. 2. Hypothesis: The mold must produce a chemical that kills the bacteria. 3. Test: Grow more of the mold separately and then return it to the bacteria. 4. Result: When the material is returned to the mold, the bacteria died. 5. Conclusion: Penicillium kills bacteria. 5. Have students read the passage at the bottom of the page and answer the GED practice question. Choice (4) is correct because the doctor saw that when the chickens ate whole‐grain rice with thiamine, they did not have the disease. Choice (1) is incorrect because the chickens were used in the experiment; they had nothing to do with the disease. There is nothing to support choice (2); the passage only mentions the conditions in the Dutch East Indies. (In fact, beriberi was widespread.) Choice (3) is incorrect because the passage points out that before the experiments, scientists incorrectly thought beriberi was caused by bacteria. Choice (5) is incorrect because the doctor found that the polished rice lacked thiamine, so the two types of rice don’t have the same nutritional value.

GED 2014 SP.1.b Understand and explain the basic features of a scientific hypothesis or Science investigation and verify claims based on evidence provided. (GED® Assessment Guide Practices for Educators, p. 62)

Activity  Pre‐GED Workbook Science : Hypotheses, pp. 16‐17, Conclusions, pp. 18‐19, Think Correlated to Like a Scientist, pp. 40‐41 New Readers  GED Science: Analysis Questions, pp. 58‐61, Evaluation Questions pp. 62‐65 Press GED  GED Scoreboost: Draw Conclusions, pp. 20‐21 2002  Pass the GED Science Test, The Scientific Method, p.45 Workbooks Using the Scientific Method

1. Read the passage and fill in the Scientific Method chart.

How Penicillin Was Discovered

In 1928, Sir Alexander Fleming was studying Staphylococcus bacteria growing in culture dishes. He noticed that a mold called Penicillium was also growing in some of the dishes. A clear area existed around the mold because all the bacteria that had grown in this area had died. In the culture dishes without the mold, no clear areas were present.

Fleming hypothesized that the mold must be producing a chemical that killed the bacteria. He decided to isolate this substance and test it to see if it would kill bacteria.. Fleming transferred the mold to a nutrient broth solution. This solution contained all the materials the mold needed to grow. After the mold grew, he removed it from the nutrient broth. Fleming then added the nutrient broth in which the mold had grown to a culture of bacteria. He observed that the bacteria died.

1. What was the observation?

2. What was the hypothesis?

3. How was the hypothesis tested?

4. What was the result of the experiment?

5. What conclusion could be drawn?

2. Answer the GED‐type question based on the Scientific Method.

In 1887 a strange nerve disease attacked the people in the Which of the following conclusions is based on the Dutch East Indies. The disease was beriberi. Symptoms of experiment described in the passage? the disease included weakness and loss of appetite; victims often died of heart failure. Scientists thought the disease (1) Humans can catch beriberi from diseased might be caused by bacteria. They injected chickens with chickens. bacteria from the blood of patients with beriberi. The (2) Beriberi only occurs in the Dutch East Indies. injected chickens became sick. However, so did a group of (3) Scientists have not yet determined which chickens that were not injected with bacteria. bacteria cause beriberi. (4) Adequate intake of thiamine prevents beriberi One of the scientists, Dr. Eijkman, noticed something. disease. Before the experiment, all the chickens had eaten whole‐ (5) Whole grain rice and polished rice have grain rice, but during the experiment, the chickens were equivalent nutritional value. fed polished rice. Dr. Eijkman researched this interesting case. he found that polished rice lacked thiamine, a vitamin necessary for good health.

Reading Selections: http://www.biologycorner.com/worksheets/scientificmethodstories.html This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United SStates License.