Logical Reasoning

PT116 · S3 · Q23 Each of many different human

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Each of many different human hormones can by itself raise the concentration of glucose in the blood.

Conclusion (probably)

The reason that every human hormones has the power to raise glucose in the blood is probably a metabolic quirk of the brain.

Evidence (to see this, consider)

Brain cells can use only glucose. So if blood glucose falls too low, brain cells will starve, resulting in unconsciousness and death.

Evaluate

This is a famously hard Main Conclusion question. Whenever we read Main Conclusion we prime our brain to listen for a Conclusion that comes earlier than its Supporting ideas, because 85% or more of the time that's where we find the Conclusion on Main Conclusion questions.

In particular, we usually see the conclusion be - the first sentence, or - some sort of rebuttal

The first sentence does kind of seem like it could be the Conclusion, because if we were to ask, , then the rest of the paragraph would seem like a response.

But the first sentence is a science fact, not an opinion. Science facts can't be our Conclusion.

The word "probably" in the second sentence indicates that it's an Opinion. The support indicator "to see this, consider" shows us that the final two sentences are trying to support this 2nd sentence.

The "thus" in the final sentence also indicates either a Conclusion or a Cause/Effect relationship.

Conclusion "thus" Sam likes my dog. Thus, Sam must be a dog lover.

Causal "thus" Sam fell off his roof and thus broke his leg.

Because the last two sentences are telling us biological facts, the final claim about "if no glucose, then death" seems more like a Cause/Effect statement than a reasoning conclusion.

But whichever we would call it, it would still just be an Intermediate Conclusion, because the final two sentences stand in support of the 2nd sentence.

Goal

Since we've identified the 2nd sentence as the foremost Opinion the author is Supporting, we're just looking for an answer choice that matches the 2nd sentence in meaning.

23.

Which one of the following most accurately expresses the main conclusion of the argument above?

  1. Each of many different human

    Fact, not Opinion

    The easiest way to talk ourselves out of believing this is a conclusion is to recognize that it is being presented as an established scientific fact about our bodies. If we were to ask, why should we believe that "every hormone can by itself raise glucose"? the support would sound like Because ... in a lab, we tested adrenaline, and endocrine, and insulin, and estrogen, and every one of these hormones was able in an isolated setting to raise the level of glucose in blood. We don't have any support for the first sentence, because it's not a conclusion. It's just being presented as an established background fact.

    16% picked this

  2. Correct

    The reason that many different

    Why this is right

    This provides a great meaning match for the 2nd sentence, which was the Main Conclusion.

    Skill tested: Main Conclusion · how this choice captures the argument's function is the move to repeat next time.

    62% picked this

  3. Although most human cells can

    Premise

    This, again, is presented as an established science fact, not the author's opinion. No evidence is offered to help convince us that brain cells can produce energy only from glucose. And this claim is prefaced by a Support Indicator, "to see [that my CONCLUSION is true], consider [my evidence]"

    2% picked this

  4. If blood glucose levels fall

    Intermediate Conclusion Last Claim Trap

    The conclusion on Main Conclusion is usually not found in the final claim (unless it's an easy problem), so we want to be wary before picking an answer that looks like the last claim. As discussed in the evaluation, this claim is debatably even a reasoning conclusion. It sounds more like a science-y cause/effect claim. And either way, this claim is part of the Support for the 2nd sentence. The author is saying, "Because brains only metabolize glucose and would die without it, that's probably why every hormone has the power to raise glucose levels".

    16% picked this

  5. The reason brain cells starve

    Never Said

    This is an implicit Inference we can derive from reading the last two sentences, whereas on Main Conclusion we want an answer to regurgitate the explicitly drawn conclusion. Also, these last two sentences are there as support to help us "see" the truth of the 2nd sentence, which is the author's opinionated conclusion.

    4% picked this

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