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DollyS
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A neuron needs to travel to the place in the brain Updated on: 26 May 2014, 01:37
Originally posted by DollyS on 26 May 2014, 00:03.
Last edited by DollyS on 26 May 2014, 01:37, edited 2 times in total.
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A neuron needs to travel to a particular place in the brain to do its work. Not all neurons are successful in their journey. Scientists think that only a third reach their destination. Some cells die during the process of neuronal development. Some neurons survive the trip, but end up where they should not be. Mutations in the genes that control migration create areas of misplaced or oddly formed neurons that can cause disorders such as childhood epilepsy or mental retardation. Thus, it can be concluded that misguided neurons are partly responsible for schizophrenia and the learning disorder dyslexia.

The argument assumes which of the following?

A. A disorder in a person does not affect the mutations in the genes in that person.
B. Genetic factors are not a significant cause of disorder such as childhood epilepsy or mental retardation.
C. Two third of the neurons do not reach their destination
D. No factor other than misguided neurons has an impact on disorders.
E. People with no disorder will not have areas of misplaced neurons.

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A
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A neuron needs to travel to the place in the brain 26 May 2014, 00:12
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A seems good here : A disorder in a person does not affect the mutations in the genes in that person

negation of reversal causation is one of the assumptions in causal arguments
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A neuron needs to travel to the place in the brain 26 May 2014, 23:21
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A seems good here : A disorder in a person does not affect the mutations in the genes in that person

negation of reversal causation is one of the assumptions in causal arguments
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Hi Aditya8062

Your explanation is very crisp and clear. :)

Thanks!
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A neuron needs to travel to the place in the brain 26 May 2014, 23:25
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Hi Folks

I was wondering if we could discuss other options as well.

Please share your views!

Thanks!
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A neuron needs to travel to the place in the brain 27 May 2014, 00:50
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Hi Folks

I was wondering if we could discuss other options as well.

Please share your views!

Thanks!
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kindly tell ur specific doubt so that i can discuss that choice in particular
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A neuron needs to travel to the place in the brain 30 May 2014, 07:55
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How are "childhood epilepsy or mental retardation" connected to "schizophrenia and the learning disorder dyslexia"?
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A neuron needs to travel to the place in the brain 22 Oct 2016, 21:46
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DollyS
A neuron needs to travel to a particular place in the brain to do its work. Not all neurons are successful in their journey. Scientists think that only a third reach their destination. Some cells die during the process of neuronal development. Some neurons survive the trip, but end up where they should not be. Mutations in the genes that control migration create areas of misplaced or oddly formed neurons that can cause disorders such as childhood epilepsy or mental retardation. Thus, it can be concluded that misguided neurons are partly responsible for schizophrenia and the learning disorder dyslexia.

The argument assumes which of the following?

A. A disorder in a person does not affect the mutations in the genes in that person.
B. Genetic factors are not a significant cause of disorder such as childhood epilepsy or mental retardation.
C. Two third of the neurons do not reach their destination
D. No factor other than misguided neurons has an impact on disorders.
E. People with no disorder will not have areas of misplaced neurons.
Show more

Cause - Effect
Mutations misplace neurons -> misplaced neurons can cause disorder
reversal
disorder affects mutations
Hence A
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A neuron needs to travel to the place in the brain 26 Oct 2016, 20:20
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Hi guys!

My analysis is below:

Conc: Misguided Ns are a "partial" a cause for Schi and the learning disorder Dys.
P1&2: Not all Ns are successful in their journey to other parts of the B to do their job.
P3: Researchers: only 1/3 of Ns reach destination.
P4: Some cells die during the development of Ns.
P5: Mut in Gs that control migration of N creates areas of misplaced or odd Ns --> cause disorders: Child E & Mental R

Pre-thinking assumptions:
-there are other partial causes (aside from misguided Ns) for disorders.
-Disorders don't have effect in Mut in Genes that creates ares of misplaced or odd N. (No reversal causation)

A) Correct!. If negated breaks the conclusion apart. Aligned with 2nd assumption
B) Irrelevant. If Genetic factors are not a significant cause of D, there might be other causes along with misguided N.
C) Incorrect. It is invalidating a premise. We have to take premises as 100% reliable information.
D) Opposite. This choice actually kind of weakens the conclusion. It says that N are the only factor affecting disorders. But, according to the argument, misguided N are partially responsible for disorders.
E) OFS. Not concern about people with no disorders. Not mention in argument. we can not assume something about this group of people

Any feedback about the Answer choices analysis??
Thanks!
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A neuron needs to travel to the place in the brain 22 Jan 2018, 04:41
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Cause & Effect argument: X causes Y (Premise) and hence X causes Z (Conclusion) what is the assumption here? - Z should not cause X

Choice C perfectly helps to break the conclusion when negated by saying it is the disorder in a person that actually affects the mutations in the genes of that person.

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A neuron needs to travel to the place in the brain 01 Mar 2018, 05:07
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Rumikido3
Hi guys!

My analysis is below:

Conc: Misguided Ns are a "partial" a cause for Schi and the learning disorder Dys.
P1&2: Not all Ns are successful in their journey to other parts of the B to do their job.
P3: Researchers: only 1/3 of Ns reach destination.
P4: Some cells die during the development of Ns.
P5: Mut in Gs that control migration of N creates areas of misplaced or odd Ns --> cause disorders: Child E & Mental R

Pre-thinking assumptions:
-there are other partial causes (aside from misguided Ns) for disorders.
-Disorders don't have effect in Mut in Genes that creates ares of misplaced or odd N. (No reversal causation)

A) Correct!. If negated breaks the conclusion apart. Aligned with 2nd assumption
B) Irrelevant. If Genetic factors are not a significant cause of D, there might be other causes along with misguided N.
C) Incorrect. It is invalidating a premise. We have to take premises as 100% reliable information.
D) Opposite. This choice actually kind of weakens the conclusion. It says that N are the only factor affecting disorders. But, according to the argument, misguided N are partially responsible for disorders.
E) OFS. Not concern about people with no disorders. Not mention in argument. we can not assume something about this group of people

Any feedback about the Answer choices analysis??
Thanks!
Show more

Hi! why does C invadilate the premise? in the passages, it says that Scientists think that only a third reach their destination.
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A neuron needs to travel to the place in the brain 02 Mar 2018, 04:28
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DollyS
A neuron needs to travel to a particular place in the brain to do its work. Not all neurons are successful in their journey. Scientists think that only a third reach their destination. Some cells die during the process of neuronal development. Some neurons survive the trip, but end up where they should not be. Mutations in the genes that control migration create areas of misplaced or oddly formed neurons that can cause disorders such as childhood epilepsy or mental retardation. Thus, it can be concluded that misguided neurons are partly responsible for schizophrenia and the learning disorder dyslexia.

The argument assumes which of the following?

A. A disorder in a person does not affect the mutations in the genes in that person. This is good. Option says us that a disorder does not cause the misguided neurons (reverse). If it were true, out conclusion would not hold. Because "bad neurons" ---> "disorder and "disorder ---> "mutations in genes" ---> "bad neurons" are contradictory to one another""
B. Genetic factors are not a significant cause of disorder such as childhood epilepsy or mental retardation. This is not true. The passage gives us information, that mutations in genes can cause sidorders ----> can not be an assumption
C. Two third of the neurons do not reach their destination. As I see it: scientists think that 1/3 reach destination, it means that 2/3 - not; it is given in a passge, so we can not count that this is an assumption
D. No factor other than misguided neurons has an impact on disorders. It is simply not true. The conclusion says that such neurons are partly responsible, so maybe there are some other reasons that are responsible ti0 ----> it can not be our assumption
E. People with no disorder will not have areas of misplaced neurons. Out of scope. We speak about people wih disorder and not otherwise
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A neuron needs to travel to the place in the brain 02 Mar 2018, 20:45
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DollyS
A neuron needs to travel to a particular place in the brain to do its work. Not all neurons are successful in their journey. Scientists think that only a third reach their destination. Some cells die during the process of neuronal development. Some neurons survive the trip, but end up where they should not be. Mutations in the genes that control migration create areas of misplaced or oddly formed neurons that can cause disorders such as childhood epilepsy or mental retardation. Thus, it can be concluded that misguided neurons are partly responsible for schizophrenia and the learning disorder dyslexia.

The argument assumes which of the following?

A. A disorder in a person does not affect the mutations in the genes in that person.
B. Genetic factors are not a significant cause of disorder such as childhood epilepsy or mental retardation.
C. Two third of the neurons do not reach their destination
D. No factor other than misguided neurons has an impact on disorders.
E. People with no disorder will not have areas of misplaced neurons.

Cause - Effect
Mutations misplace neurons -> misplaced neurons can cause disorder
reversal
disorder affects mutations
Hence A
Show more

Hi,
I am unable to understand...I understood the cause effect..Mutations mispace neurons which cause disorder...Didnot understand the reversal. Option A says ....disorder doesnot affect mutations....Here I am lost.Can you please help???
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A neuron needs to travel to the place in the brain 03 Mar 2018, 04:07
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DollyS
A neuron needs to travel to a particular place in the brain to do its work. Not all neurons are successful in their journey. Scientists think that only a third reach their destination. Some cells die during the process of neuronal development. Some neurons survive the trip, but end up where they should not be. Mutations in the genes that control migration create areas of misplaced or oddly formed neurons that can cause disorders such as childhood epilepsy or mental retardation. Thus, it can be concluded that misguided neurons are partly responsible for schizophrenia and the learning disorder dyslexia.

The argument assumes which of the following?

A. A disorder in a person does not affect the mutations in the genes in that person.
B. Genetic factors are not a significant cause of disorder such as childhood epilepsy or mental retardation.
C. Two third of the neurons do not reach their destination
D. No factor other than misguided neurons has an impact on disorders.
E. People with no disorder will not have areas of misplaced neurons.

Cause - Effect
Mutations misplace neurons -> misplaced neurons can cause disorder
reversal
disorder affects mutations
Hence A

Hi,
I am unable to understand...I understood the cause effect..Mutations mispace neurons which cause disorder...Didnot understand the reversal. Option A says ....disorder doesnot affect mutations....Here I am lost.Can you please help???
Show more

1. What does the passage say?
"mutations in genes" -----> "bad neurons" ---> "disorder"

2. What does option A say?
"disorder" does NOT cause "mutations in genes" and thus does not cause "bad neurons".

If we negate option A, we get this:
"disorder" -----> "mutations in genes" ----> "bad neurons".

So the chain in item 1 does not stand. Conclusion falls apart.
"mutations in genes" -----> "bad neurons" ---> "disorder"
"disorder" -----> "mutations in genes" ----> "bad neurons".
These are reversal chains.

So option A is an answer.
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A neuron needs to travel to the place in the brain 08 Sep 2019, 07:24
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DollyS
A neuron needs to travel to a particular place in the brain to do its work. Not all neurons are successful in their journey. Scientists think that only a third reach their destination. Some cells die during the process of neuronal development. Some neurons survive the trip, but end up where they should not be. Mutations in the genes that control migration create areas of misplaced or oddly formed neurons that can cause disorders such as childhood epilepsy or mental retardation. Thus, it can be concluded that misguided neurons are partly responsible for schizophrenia and the learning disorder dyslexia.

The argument assumes which of the following?

A. A disorder in a person does not affect the mutations in the genes in that person.
B. Genetic factors are not a significant cause of disorder such as childhood epilepsy or mental retardation.
C. Two third of the neurons do not reach their destination
D. No factor other than misguided neurons has an impact on disorders.
E. People with no disorder will not have areas of misplaced neurons.
Show more

ARGUMENT
[con] misguided neurons are PARTLY responsible for disorders; [prem] because mutations in the genes create areas of misplaced or oddly formed neurons that can cause disorders.

ASSUMPTION
assumes that mutations in the genes create such neurons that cause such disorders [mutations = bad neurons = disorders]; and that the inverse is not true [disorders = mutations = bad neurons].

B. not mentioned, irrelevant; out.
C. "scientists THINK that only 1/3 reach their destination" the author assumes that 1/3 is a possibility, but not a certainty, thus we cannot assume that 2/3 do not reach their destination; out.
D. "misguided neurons are PARTLY responsible" thus other factors might exist; out.
E. "create areas that CAN cause disorders" doesn't mean there aren't any such areas; out.

Answer (A)
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A neuron needs to travel to the place in the brain 29 Mar 2024, 21:33
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A doesn't seem to follow for me. "A disorder in a person does not affect the mutations in the genes in that person" -- gene formation comes before the development of a person... so there will be no way "disorder" comes before "gene formation". it does not need to be assumed?
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This is not a valid question. When an argument claims that X is "partly responsible" for Y, that doesn't mean they are assuming Y cannot cause X. In fact, it's quite normal to see loops of causation. After all, isn't that where war comes from? X attacks Y because Y attacked X because X antagonized Y," etc.

Additionally, necessary assumptions should not generalize from the narrow cases in question to all cases. If I think that my cousin missed my birthday party because they made other plans, that doesn't mean that no one ever makes other plans because they missed a social event.

Overall, the author of the question seems to have mixed up assumption and strengthen. There are also other flaws that get in the way of A working as an answer, but I'm not sure I need to pile them all on. Rather, I'll repeat my usual advice that you are best off learning verbal from official questions, and that in some cases, random "fan-made" questions may actually impede your learning.

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