CR question

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CR question

by iamcste » Mon Apr 20, 2009 4:14 pm
In humans, ingested protein is broken down into amino acids, all of which must compete to enter the brain. Subsequent ingestion of sugars leads to the production of insulin, a hormone that breaks down the sugars and also rids the bloodstream of residual amino acids, except for tryptophan, Tryptophan then slips into the brain uncontested and is transformed into the chemical serotonin, increasing the brain's serotonin level. Thus, sugars can play a major role in mood elevation, helping one to feel relaxed and anxiety-free.

Which one of the following is an assumption on which the argument depends?

(A) Elevation of mood and freedom from anxiety require increasing the level of serotonin the brain.
(B) Failure to consume foods rich in sugars results in anxiety and a lowering of mood.
(C) Serotonin can be produced naturally only if tryptophan is presented in the bloodstream.
(D) Increasing the level of serotonin in the brain promotes relaxation and freedom from anxiety.
(E) The consumption of protein-rich foods results in anxiety and a lowering of mood.

can anyone explain why option A is incorrect, I have some clues but wanted to ensure that I do not miss any thing important

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by gmat740 » Mon Apr 20, 2009 6:39 pm
The Question goes like this

Sugar=>Insulin(breaks Sugar and wipes out amino)=>Only T enters Brain=>Transformed to S=> Brain's S-level Increase

conclusion:
Sugar=> mood elevation

Missing link between premise and conclusion

Brain's S-level Increase => mood elevation

So, answer is D


A. this is reverse of the answer we are looking for

mood elevation => Brain's S-level Increase
So A is incorrect

Hope this Helps

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by iamcste » Mon Apr 20, 2009 6:55 pm
gmat740 wrote:
A. this is reverse of the answer we are looking for

mood elevation => Brain's S-level Increase
So A is incorrect
do you understand from option A that Increasing S is the only way for mood elevation?

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by gmat740 » Mon Apr 20, 2009 7:23 pm
do you understand from option A that Increasing S is the only way for mood elevation?
Option A is the exaggeration of Option D
A) Elevation of mood and freedom from anxiety require increasing the level of serotonin the brain
Require: extreme word.

Actually we can think this way

X causes Y

But does this mean Y is caused only by X?

Hope now it is clear

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by lunarpower » Tue Apr 21, 2009 12:10 am
gmat740 nails it.

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i can't really explain any better than gmat740 did, so, to round things out, i'll just give an analogy.

analogy:

if you come over to my place, i'll give you a big fat steak. therefore, if you come over to my place, you'll be full and happy.

option (a), on this problem, would say that being full and happy REQUIRES a fat steak. this is obviously absurd, since there are plenty of other ways to get full and happy.
mmm... fish and chips.

option (d) would say that a big fat steak will make you full and happy, which is definitely an operative assumption here.

same deal on your question.
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by iamcste » Tue Apr 21, 2009 2:26 am
gmat740 wrote:
Require: extreme word.

Thanks buddy for your inputs. Whats the source for this?

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by bluementor » Tue Apr 21, 2009 5:10 am
Whats wrong with option B?

-BM-

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by lunarpower » Wed Apr 22, 2009 12:37 am
bluementor wrote:Whats wrong with option B?

-BM-
one major problem with that choice is the phrase "foods rich in sugars", a concept that is net referenced anywhere in the passage.

remember the mentality that you have to have to succeed on these questions: if any two things are at all different, then you have to think of them as completely unrelated.
this is a difficult thing to do, but it's absolutely necessary for success on these problem types, as they tend to play heavily on subtle differences.

in this problem, "consumption of sugars", in your mind, should have NOTHING to do with eating foods that are rich in sugars. therefore, this is a non sequitur.

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the other problem is that this wouldn't follow anyway. if the eating of sugar leads to elevation of mood and/or lack of anxiety, it doesn't follow that not eating sugar will produce the opposite. that would only be the case if sugar ingestion were the only way to raise mood / get rid of anxiety, which isn't stated anywhere in the passage.

analogy:
if a fat steak makes me feel full and happy, it does NOT follow that not eating a fat steak will ensure that i am not full or happy. again, i could produce the same effect with a nice plate of fish and chips.

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also, let's not forget that you're looking for an aassumption here. an assumption is an extra statement that, when added to the passage, completes the argument.
this statement is more like a (faulty attempt at a) conclusion of the argument, which isn't what we're after at all.
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by Brad.C » Sun May 15, 2016 6:33 am
I also think answer is D

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question

by nitesh50 » Tue Dec 04, 2018 7:38 pm
In humans, ingested protein is broken down into amino acids, all of which must compete to enter the brain. Subsequent ingestion of sugars leads to the production of insulin, a hormone that breaks down the sugars and also rids the bloodstream of residual amino acids, except for tryptophan. Tryptophan then slips into the brain uncontested and is transformed into the chemical serotonin, increasing the brain's serotonin level. Thus sugars cause mood elevation, helping one to feel relaxed and anxiety-free.

Which one of the following is an assumption on which the argument depends?

(A) Elevation of mood and freedom from anxiety require increasing the level of serotonin the brain.
(B) Failure to consume foods rich in sugars results in anxiety and a lowering of mood.
(C) Serotonin can be produced naturally only if tryptophan is presented in the bloodstream.
(D) Increasing the level of serotonin in the brain promotes relaxation and freedom from anxiety.
(E) The consumption of protein-rich foods results in anxiety and a lowering of mood.

For this Q can all A,B & D be correct answers?
CR bible says when we have causal reasoning as in this modified Q, effect(mood elevation) occurs only when cause(sugar) occurs.
And in such Qs assumption question is similar to strengthen question for which correct answer fits "cause doesn't occur, effect doesn't occur" category.
I am changing B(which originally is like "no cause, OPPOSITE effect" to
B) Mood elevation is not observed in people who consume foods not rich sugar.
Now it is "no cause, no effect". Does that mean this is also a correct answer?

Also according to CR bible, since this causal reasoning Q, sugar is the only reason for mood elevation.
That means even A should answer the Q.
What do you think?


Can some experts weigh in on this thought process?

Regards
Nitesh