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 and found that polished rice lacked thiamine, a vitamin necessary for good health.
1. State the Problem.
Answer: There was a strange disease back in 1887 that attacked the people in the Dutch East Indies called beriberi.
2. What was the hypothesis?
Scientists thought the disease might be caused by bacteria.
3. How was the hypothesis tested?
Scientists injected chickens with bacteria from the blood of patients with beriberi in order to test the hypothesis.
4. Should the hypothesis be supported or rejected based on the experiment?
5. What should be the new hypothesis and how would you test it?
I am stuck on how do I answer number 4 and 5 or how do I begin to learn how to answer number 4 and 5?
Please advise and let me know if I got 1-3 correct.
1-3 Right
4. Rejected
5. Lack of thiamine causes beriberi.
New set of chickens fed whole grain or polished rice.
Wow! Thank you so very much for your help. Now I know that I was definitely on the right track with this and got my answers right.
I appreciate all of your help.
I found out that hypothesis is basically a prediction.
How long have you been doing Science?
You have correctly answered questions 1-3. However, let's proceed with questions 4 and 5:
4. Should the hypothesis be supported or rejected based on the experiment?
Based on the experiment conducted, the hypothesis that beriberi is caused by bacteria should be rejected. The reason for this is that even the group of chickens that were not injected with bacteria still became sick. This suggests that bacteria alone may not be the direct cause of beriberi.
5. What should be the new hypothesis and how would you test it?
Since the previous hypothesis that beriberi is caused by bacteria has been rejected, a new hypothesis needs to be formulated. Given Dr. Eijkman's observation about polished rice lacking thiamine, a possible new hypothesis could be that beriberi is caused by a deficiency of thiamine.
To test this new hypothesis, an experiment could be set up where two groups of chickens are fed different diets. One group would be fed a diet containing polished rice (lacking thiamine), while the other group would be fed a diet containing whole-grain rice (containing thiamine). Observations and measurements could be taken to track the health and development of the chickens in both groups. If the group fed polished rice shows symptoms similar to beriberi, such as weakness and loss of appetite, while the group fed whole-grain rice remains healthy, it would provide evidence to support the new hypothesis.
Great job on answering questions 1-3! You have correctly identified the problem and stated the hypothesis and the method used to test it.
Now, let's move on to questions 4 and 5:
4. Should the hypothesis be supported or rejected based on the experiment?
Based on the experiment, the hypothesis that beriberi is caused by bacteria should be rejected. This is because not only the injected chickens, but also a group of chickens that were not injected with bacteria, became sick. This suggests that the bacteria alone cannot explain the cause of the disease. Therefore, the hypothesis that beriberi is caused by bacteria is not supported.
5. What should be the new hypothesis and how would you test it?
The new hypothesis that can be derived from the results of the experiment is that the disease beriberi is caused by a dietary deficiency, specifically the lack of thiamine, a vitamin necessary for good health.
To test this new hypothesis, you could conduct an experiment with two groups of chickens. One group would be fed a diet containing polished rice (which lacks thiamine), while the other group would be fed a diet containing whole-grain rice (which contains thiamine). The chickens would then be observed for symptoms of beriberi, such as weakness and loss of appetite. If the group of chickens fed polished rice shows a higher incidence of beriberi symptoms compared to the group fed whole-grain rice, it would support the new hypothesis that thiamine deficiency is the cause of beriberi.
To further confirm the hypothesis, you could conduct similar experiments with other animals or even human subjects, following the same approach of providing diets with and without thiamine to observe the effects on their health.
I hope this helps you answer questions 4 and 5! Let me know if there's anything else I can assist you with.