Exercise 7 - SACS Scientific Method

Bio 1111 Principles of Bio Lab Report

Below are two examples of how scientists use the Scientific Method to conduct research.  

Read & Complete the following report form by answering the questions in Part A & B.

Part A.  “The Strange Case of BeriBeri”

In 1887 a strange nerve disease attacked the people in the Dutch East Indies. The disease was beriberi. Symptoms of the disease included weakness and loss of appetite, victims often died of heart failure. Scientists thought the disease might be caused by bacteria. They injected chickens with bacteria from the blood of patients with beriberi. The injected chickens became sick. However, so did a group of chickens that were not injected with bacteria.

One of the scientists, Dr. Eijkman, noticed something. Before the experiment, all the chickens had eaten whole-grain rice, but during the experiment, the chickens were fed polished rice. Dr. Eijkman researched this interesting case. He found that polished rice lacked thiamine, a vitamin necessary for good health.

 Answer the questions and follow instructions below to submit form for Part A.

1. State the Problem.
2. What was the hypothesis? Include any background information that related to the formation of this hypothesis.
3. How was the hypothesis tested? Include any methods or materials that the scientist used in the experiment.
4. Should the hypothesis be supported or rejected based on the experiment? Include the results of the experiment and any discussion you feel that is relevant to support or deny the hypothesis.
5. Conclusion: What should be the new hypothesis?

Part B: “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.

 Answer the questions and follow instructions below to submit form for Part B.

1. Identify the problem.
2. What was Fleming's hypothesis? Include any background information that related to the formation of this hypothesis.
3. How was the hypothesis tested? Include any methods or materials that the scientist used in the experiment.
4. Should the hypothesis be supported or rejected based on the experiment? Include the results of the experiment and any discussion you feel that is relevant to support or deny the hypothesis.
5. Conclusion: What should be the new hypothesis? (This experiment leads to the development of what major medical advancement?)