Logical Reasoning

PT109 · S3 · Q20 Galanin is a protein found

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Galanin is a protein found in the brain.

Conclusion (these facts support)

Galanin causes rats to crave fatty foods.

Evidence

In an experiment, rats that consistently chose to eat fatty foods when offered a choice between lean and fatty foods were found to have significantly higher concentrations of galanin in their brains than did rats that consistently chose lean over fatty foods.

Evaluate

This argument fits the Explain Curious Fact pattern because it highlights a correlation between galanin levels and a preference for fatty foods.

Curious Fact Why do rats that choose fatty foods have higher concentrations of galanin?

Author's Explanation Galanin causes rats to crave fatty foods.

To strengthen this argument, we can either increase the plausibility of the author's explanation or rule out alternate explanations.

With correlation to causality arguments like this, we know to always consider the alternate explanations of Reverse Causality (maybe eating fatty foods put galanin in their brain) or Third Factor (maybe some other thing, like a DNA mutation, is connected to choosing fatty foods and connected to high galanin)

Goal

Let's find an answer that makes it more plausible that galanin leads to fat cravings, or one that rules out an alternate explanation for why galanin was correlated with eating fatty foods.

20.

Which one of the following, if true, most supports the argument?

The craving for fatty foods
No Impact / Too Weak
This just says there is at least one time when a rat had a craving for fatty food but still chose a lean food. That doesn't tell us anything about whether galanin caused the craving, nor does it address an alternate explanation for why galanin and fatty foods are correlated.
3% picked this
The brains of the rats
Irrelevant Comparison
The amount of fat in the brains of rats compared to other rats doesn't address whether galanin causes cravings for fatty foods. This doesn't provide information about the role of galanin as a causal factor in food preference. We were never talking about fat in the brain, so this is just a Word Salad.
5% picked this
The chemical components of galanin
Weaker Impact
An alternate explanation for why galanin and eating fatty foods were correlated could be that eating fatty foods causes galanin to go in your brain. This answer sort of seems to undermine that, because it would be saying, "No galanin isn't a special ingredient of fatty foods. It's in fatty and lean." But it says the chemical components of galanin, not galanin. The chemical components of water are Hydrogen and Oxygen, but just because you have hydrogen and oxygen in something doesn't mean you have water. Also, even if this were saying galanin is present in both fatty and lean foods, we still wouldn't know to what degree in each food. (i.e. water is present in both peanuts and watermelon, but it's present to a much higher degree in watermelon). So this answer still very much allows for the alternate explanation that fatty foods are high in galanin, and so THAT'S the real reason for the correlation. Since it doesn't really rule out an alternate explanation, it barely strengthens, if at all.
2% picked this
Correct
The rats that preferred fatty
Why this is right
If the rats that preferred fatty foods had higher concentrations of galanin before being offered fatty foods, this suggests that galanin is not just a result of eating fatty foods but could be a causal factor influencing their preference. It rules out the possibility of reverse causation (that eating fatty foods increases galanin) and supports the idea that galanin leads to a craving for such foods.
Skill tested: Strengthen · how this choice captures the argument's function is the move to repeat next time.
84% picked this
Rats that metabolize fat less
Opposite (if anything)
If metabolizing fat less efficiently causes rats to develop high concentrations of galanin, this could be an alternate explanation for the higher galanin levels found in rats that choose fatty foods. In this scenario, galanin might be a result of inefficient fat metabolism rather than a cause of a craving for fatty foods.
6% picked this

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