To analyze:
An experimental design to test whether probiotic drinks can help with "slow intestinal transit time"and help "prevent cold and flu".
Introduction:
The Dannon company claims that its Activia yogurt helps with "slow intestinal transit time" and DanActive dairy drink helps "prevent cold and flu". Therefore, these claims need to be tested experimentally.
Explanation of Solution
Since two products are being tested for their claims, two experiments need to be conducted. In each experiment, the participants receiving the product must be divided into two groups, with one receiving the product and the other receiving an inert substitute (that has no effect, but looks and tastes the same as the product). The experiments must be double-blind (the participants and the health professional giving these products do not know which participants are consuming the product and which participants are consuming the inert substitute).
The steps to test Activia yogurt consist of the following:
- The participants are divided into two groups – a control group called group 1 and an experiment group called group 2.
- The control group is given an inert yogurt substitute, which does not offer any effect.
- The experiment group is given Activia yogurt.
- The intestinal transit time is measured for both groups.
- If the intestinal transit time is faster for participants in group 2 (experiment group) than for those in group 1 (control group), this means the claims about Activia yogurt are true.
The steps to test DanActive dairy drink consist of the following:
- The participants are again divided into two groups – a control group called group 1 and an experiment group called group 2.
- The control group is given an inert dairy drink substitute, which does not offer any effect.
- The experiment group is given DanActive dairy drink.
- The test groups are exposed to the cold or flu viruses.
- If the experiment group has lower occurrence of cold and flu than the control group, the claims about DanActive dairy drink are true.
By conducting double-blind experiments, using control and experiment groups, and critically testing whether the claims of Dannon company are true, the claims about their products Activia yogurt drink and DanActive dairy drink can be verified.
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Chapter 1 Solutions
Loose-leaf Version for What is Life? A Guide to Biology
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