potato cyst

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potato cyst

by crazy4gmat » Tue Nov 11, 2008 10:40 am
Potato cyst nematodes are a pest of potato crops. The nematodes can lie dormant for several years in their cysts, which are protective capsules, and do not emerge except in the presence of chemicals emitted by potato roots. A company that has identified the relevant chemicals is planning to market them to potato farmers to spread on their fields when no potatoes are planted; any nematodes that emerge will soon starve to death.
Which of the following, if true, best supports the claim that the company’s plan will be successful?
(A) Nematodes that have emerged from their cysts can be killed by ordinary pesticides.
(B) The only part of a potato plant that a nematode eats is the roots.
(C) Some bacteria commonly present in the roots of potatoes digest the chemicals that cause the nematodes to emerge from their cysts.
(D) Trials have shown that spreading even minute quantities of the chemicals on potato fields caused nine-tenths of the nematodes present to emerge from their cysts.
(E) The chemicals that cause the nematodes to emerge from their cysts are not emitted all the time the potato plant is growing.
Source: — Critical Reasoning |

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by Stockmoose16 » Thu Nov 13, 2008 12:18 am
The OA for this question is apparently D, but the conclusion states that the nemotoids will STARVE TO DEATH. D simply says the nemotoids will emerge from the ground, it says nothing about them dying.

B seems like the better choice, because it specifically shows that the nemotoids would die as a result of no food (a lack of potato root).

Can anyone explain why D is correct?

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by slash » Thu Nov 13, 2008 1:39 am
Even I feel the same.

Option B supports the argument: If only part of a potato plant that a nematode eats is the roots and no potatoes are planted obviuosly it will starve to death.

Option D: This option does not exactly support the argument, it does not support anything which is related (nematode) starve to death. It proves only the chemical will induce the nematode to emerge out of their cysts

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by gmat009 » Thu Nov 13, 2008 7:35 am
I totally agree. Answer should be B.

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by nervesofsteel » Thu Nov 13, 2008 10:52 am
The answer should be D

(B) The only part of a potato plant that a nematode eats is the roots.

In correct as it says only about potato plant ... there can be other possibilities of survival even if potato plant is not there...

As compared to D ... B is not clarifying things..

Moreover the explanation given in link pasted in earlier post is good to further clarify doubts

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by Stockmoose16 » Thu Nov 13, 2008 11:51 am
nervesofsteel wrote:The answer should be D

(B) The only part of a potato plant that a nematode eats is the roots.

In correct as it says only about potato plant ... there can be other possibilities of survival even if potato plant is not there...

As compared to D ... B is not clarifying things..

Moreover the explanation given in link pasted in earlier post is good to further clarify doubts
Completely disagree. The chemical company's argument clearly states that the nematode will starve to death. To strengthen that conclusion, we need something that proves they will starve to death, not just emerge from the ground. D does not strengthen the conclusion.

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Re: potato cyst

by sushanta57021 » Thu Nov 13, 2008 10:21 pm
crazy4gmat wrote:Potato cyst nematodes are a pest of potato crops. The nematodes can lie dormant for several years in their cysts, which are protective capsules, and do not emerge except in the presence of chemicals emitted by potato roots. A company that has identified the relevant chemicals is planning to market them to potato farmers to spread on their fields when no potatoes are planted; any nematodes that emerge will soon starve to death.
Which of the following, if true, best supports the claim that the company’s plan will be successful?
(A) Nematodes that have emerged from their cysts can be killed by ordinary pesticides.
(B) The only part of a potato plant that a nematode eats is the roots.
(C) Some bacteria commonly present in the roots of potatoes digest the chemicals that cause the nematodes to emerge from their cysts.
(D) Trials have shown that spreading even minute quantities of the chemicals on potato fields caused nine-tenths of the nematodes present to emerge from their cysts.
(E) The chemicals that cause the nematodes to emerge from their cysts are not emitted all the time the potato plant is growing.
the answer should be D:
because the question is what best supports the claim that the company’s plan will be successful?
that means what will make them successful in marketing the product or in turn convince the farmers that the product is useful. no other choices state that the company's product will useful to the farmer.
hope this helps

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Re: potato cyst

by Stockmoose16 » Fri Nov 14, 2008 1:18 am
sushanta57021 wrote:
crazy4gmat wrote:Potato cyst nematodes are a pest of potato crops. The nematodes can lie dormant for several years in their cysts, which are protective capsules, and do not emerge except in the presence of chemicals emitted by potato roots. A company that has identified the relevant chemicals is planning to market them to potato farmers to spread on their fields when no potatoes are planted; any nematodes that emerge will soon starve to death.
Which of the following, if true, best supports the claim that the company’s plan will be successful?
(A) Nematodes that have emerged from their cysts can be killed by ordinary pesticides.
(B) The only part of a potato plant that a nematode eats is the roots.
(C) Some bacteria commonly present in the roots of potatoes digest the chemicals that cause the nematodes to emerge from their cysts.
(D) Trials have shown that spreading even minute quantities of the chemicals on potato fields caused nine-tenths of the nematodes present to emerge from their cysts.
(E) The chemicals that cause the nematodes to emerge from their cysts are not emitted all the time the potato plant is growing.
the answer should be D:
because the question is what best supports the claim that the company’s plan will be successful?
that means what will make them successful in marketing the product or in turn convince the farmers that the product is useful. no other choices state that the company's product will useful to the farmer.
hope this helps
That's not true. B says that the nematodes will die (since they only eat potato root, which will no longer be available to them)

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Re: potato cyst

by sushanta57021 » Fri Nov 14, 2008 9:40 am
Stockmoose16 wrote:
sushanta57021 wrote:
crazy4gmat wrote:Potato cyst nematodes are a pest of potato crops. The nematodes can lie dormant for several years in their cysts, which are protective capsules, and do not emerge except in the presence of chemicals emitted by potato roots. A company that has identified the relevant chemicals is planning to market them to potato farmers to spread on their fields when no potatoes are planted; any nematodes that emerge will soon starve to death.
Which of the following, if true, best supports the claim that the company’s plan will be successful?
(A) Nematodes that have emerged from their cysts can be killed by ordinary pesticides.
(B) The only part of a potato plant that a nematode eats is the roots.
(C) Some bacteria commonly present in the roots of potatoes digest the chemicals that cause the nematodes to emerge from their cysts.
(D) Trials have shown that spreading even minute quantities of the chemicals on potato fields caused nine-tenths of the nematodes present to emerge from their cysts.
(E) The chemicals that cause the nematodes to emerge from their cysts are not emitted all the time the potato plant is growing.
the answer should be D:
because the question is what best supports the claim that the company’s plan will be successful?
that means what will make them successful in marketing the product or in turn convince the farmers that the product is useful. no other choices state that the company's product will useful to the farmer.
hope this helps
That's not true. B says that the nematodes will die (since they only eat potato root, which will no longer be available to them)
Bo doesn't say that nematodes will come out of the cysts because of the chemical; then why should someone buy the chemical?
and any nematodes that emerge will soon starve to death. is already mentioned in the question stem. So B is out of scope, B only strengthens the assumption of the company.
we have to get the answer that best supports the claim that the company’s plan will be successful...D says it, because we know anyway that the nematodes will starve to death once they come out.

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by amitabhprasad » Fri Nov 14, 2008 10:02 am
I picked "B" as well.
But when I think again "B" is more of an assumption on which argument is based.
If you consider that then 'D' seems correct answer choice.
Very confusing not sure whether I can make this distinction on the test day

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by Stacey Koprince » Wed Nov 19, 2008 9:51 am
I received a PM asking me to respond.

nematodes = potato pests
can lie dormant, cysts protect
chemicals from Ps make Ns emerge
company to sell P chems
C: to make Ns emerge too soon then Ns starve

strengthen

A. not about this plan
B. if anything, this weakens. Either the chemicals penetrate the earth, in which case it doesn't matter what part of the P plant the Ns are eating: the plan works but this statement doesn't strengthen it (or do anything else - we already know the Ns eat potatos, so which specific part they eat isn't relevant). Or the chemicals don't penetrate the earth, in which case they don't get to the Ns, so the plan doesn't work (so this statement weakens it)
C. Under the plan, there aren't any potato roots in the fields at the time of chemical use - so this is irrelevant.
D. The cysts are "protective" and the Ns are "dormant" while in them, so the Ns don't die while they're in the cysts. It's necessary to get them out of their cysts in order for them to starve to death. So if the farmers can spread even very small quantities and get the Ns out of their cysts when Ps aren't there, and most Ns will emerg, then the plan is likely to make most of the Ns starve to death.
E. Irrelevant. As long as the chemicals are emitted some of the time, the Ps are vulnerable to the Ns.
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by dileepsinha » Thu Nov 20, 2008 5:44 am
To add to it:

I think B could have been right if B was- nematodes eat only potatoes.
But B is different and hence the question of whether nematodes will emerge becomes crucial for the success.

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by maihuna » Fri Jan 02, 2009 12:11 pm
its all tricky it seems...in my second attempt after month too I choose answer A...I can see everybody blasting A...but just to understand more about why A is so irrelebvent can somebody please point it out...

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by Stacey Koprince » Thu Jan 08, 2009 8:49 am
The plan is:
1) a field that has NO potatoes in it
2) a chemical that makes the nematodes emerge, even though there aren't any potatoes
3) nematodes starve because there are no potatoes to eat

The question asks about the company's plan, and the company's plan is to starve the nematodes to death.

Answer A says that you can use pesticides to kill the nematodes. That may be true, but it is irrelevant to this company's plan, because this company's plan is to starve the nematodes. The fact that there is a completely different way to kill the nematodes doesn't tell us anything about whether the company's plan to starve the nematodes will work. Does that make sense?
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