Researchers studying how genes control animal

[gauravtyagigmat]

Researchers studying how genes control animal
behavior have had to deal with many uncertainties. In
the first place, most behaviors are governed by more
than one gene, and until recently geneticists had no
method for identifying the multiple genes involved. In
addition, even when a single gene is found to control a
behavior, researchers in different fields do not
necessarily agree that it is a "behavioral gene."
Neuroscientists, whose interest in genetic research is
to understand the nervous system (which generates
behavior), define the term broadly. But ethologists"”
specialists in animal behavior"”are interested in
evolution, so they define the term narrowly. They
insist that mutations in a behavioral gene must alter a
specific normal behavior and not merely make the
organism ill, so that the genetically induced behavioral
change will provide variation that natural selection can
act upon, possibly leading to the evolution of a new
species. For example, in the fruit fly, researchers have
identified the gene Shaker, mutations in which cause
flies to shake violently under anesthesia. Since shaking
is not healthy, ethologists do not consider Shaker a
behavioral gene. In contrast, ethologists do consider
the gene period (per), which controls the fruit-fly’s
circadian (24-hour) rhythm, a behavioral gene because
files with mutated per genes are healthy; they simply
have different rhythms.

The passage suggests that neuroscientists would most
likely consider Shaker to be which of the following?
A. An example of a behavioral gene
B. One of multiple genes that control a single behavior
C. A gene that, when mutated, causes an alteration in
a specific normal behavior without making the
organism ill
D. A gene of interest to ethologists but of no interest
to neuroscientists
E. A poor source of information about the nervous
system

I marked E because i was not able to figure out correct answer

A. I didn't mark because neuro scientist are interested in nerveous system

B.thats for genetic scientist

C. not related to neuro scientist..it belongs to ethologist

Confused between D and E and marked E at last

question2
It can be inferred from the passage that which of the
following, if true, would be most likely to influence
ethologists’ opinions about whether a particular gene
in a species is a behavioral gene?
A. The gene is found only in that species.
B. The gene is extremely difficult to identify.
C. The only effect of mutations in the gene is to make
the organism ill.
D. Neuroscientists consider the gene to be a
behavioral gene.
E. Geneticists consider the gene to be a behavioral
gene.

"when we say likely to influence ethologists’ opinions "

I thought which of the following create doubt in ethologist mind that a particular gene is behavioural gene or not

Please guide me many times wrongly understand passage because of tricky language and end up in marking wrong answers.
Making notes strategy mentioned Manhattan reading comprehension guide is very difficult for me to deal.As there is already less time per question and it create panic in mind.
Please suggest me should i do to improve my reading compression.
I am targeting more that 720 scrore in GMAT please helpme out.Which course material from manhattan will help me to improve my RC

[RonPurewal]

Hi,
Per the forum rules, please post the official answers to these questions.

Brief hints:

1/
The point is that the ethologists' definition is narrower than the neuroscientists' broader definition.
Given that, think about why you'd be presented an example of something that the ethologists (the people with the narrower definition) would exclude.

2/
The text states that ethologists insist that X be the case, and that Y not be the case. One of these answer choices is, almost verbatim, identical to one of those considerations.

Can't give more detail unless you provide the official answers, as required.

[RonPurewal]

Please guide me many times wrongly understand passage because of tricky language and end up in marking wrong answers.
Making notes strategy mentioned Manhattan reading comprehension guide is very difficult for me to deal.As there is already less time per question and it create panic in mind.
Please suggest me should i do to improve my reading compression.
I am targeting more that 720 scrore in GMAT please helpme out.Which course material from manhattan will help me to improve my RC

This question belongs in a separate thread, in the General GMAT Strategy folder. Please re-post it there.

(In general, any dense scientific/technical language is there as a distraction. The words you actually need to answer the problems will not be "tricky language".)

[Khush]

Hi Ron,

Even i find the aforementioned question # 1 difficult.

Let me provide the official answers to the above questions as the poster of the question is yet to respond.

OA for question #1 is A

OA for question #2 is C

I got #2 right. I felt this question is similar to an evaluate the argument question in CR. As you told above that the correct answer is a verbatim of the given text, the answer lies in the below text:
"They insist that mutations in a behavioral gene must alter a
specific normal behavior and not merely make the
organism ill...."

I chose choice B for #1. I inferred this from the below statements in the passage:

"In addition, even when a single gene is found to control a behavior, researchers in different fields do not necessarily agree that it is a "behavioral gene" . "

and

"For example, in the fruit fly, researchers have
identified the gene Shaker, mutations in which cause
flies to shake violently under anesthesia".

I rejected A in #1 as i thought it might be a Trap answer saying so just because the passage says "neurologists"and "ethologists" differ in their opinions on a topic, implying that for any experiment what is a behavioral gene for ethologists will not be the same for neurologists. Also, the passage does not explain the broad definitions of neurologists on Shaker experiment. Hence, i could not infer A.

Please help here.

[RonPurewal]

I got #2 right. I felt this question is similar to an evaluate the argument question in CR.

Your reasoning seems fine, but, if you apply the same reasoning to "evaluate this argument" questions in CR, you'll be in big, big trouble.

"Evaluate the argument" questions are basically strengthen/weaken questions that don't take sides. (E.g., if "X happens" weakens an argument, then "Whether X happens" or "Does X happen?" helps to evaluate it.)
If you just re-phrase statements that are already within the bounds of those passages, it will be impossible to solve them. Any statement that "strengthens"/"weakens"/"helps to evaluate"/"explains" something MUST be something that HAS NOT already been mentioned or implied.

This type of reasoning does, however, work to solve "draw your own conclusion" CR questions. Perhaps (hopefully), that's what you meant.

[RonPurewal]

"In addition, even when a single gene is found to control a behavior,

^^ This is evidence that the following discussion is about single genes that control a behavior. I.e., proof that choice B is wrong.

If you read the discussion of the Shaker gene, it's clear that the Shaker gene, all by itself, causes the fly to shake. That's the opposite of choice B.

"For example, in the fruit fly, researchers have
identified the gene Shaker, mutations in which cause
flies to shake violently under anesthesia".

Yep. This.
Is why (B) is wrong.

It says "mutations in (THIS ONE GENE) CAUSE flies to shake violently". It doesn't say "...among other genes", or "...can contribute to this behavior", or etc. It says "X causes Y", which means that X causes Y without help from other X's.

[RonPurewal]

I rejected A in #1 as i thought it might be a Trap answer saying so just because the passage says "neurologists"and "ethologists" differ in their opinions on a topic, implying that for any experiment what is a behavioral gene for ethologists will not be the same for neurologists.

Your attitude of suspicion is not unjustified, but you have to remember the context of the passage.
This passage is primarily concerned with the differences between these two groups' conceptions of what makes a gene behavioral. So, if the passage specifically says "This ONE group thinks X", then you should be very strongly slanted toward thinking that the OTHER group thinks... NOT x.

E.g., let's say I'm reading a paragraph about differences between the US and Saudi Arabia.
If the passage mentions that "In the United States, the traditional weekend is Saturday and Sunday", then I should absolutely expect"”and infer"”that the Saudi weekend will fall on different days. If not, then the entire structure of the passage would be completely misleading and/or self-defeating.

In any case, if you need hard proof, it's there.
The passage says that neurologists classify genes as behavioral if they control any behavior generated by the nervous system"”i.e., pretty much anything that an animal ever does.
The shaking is definitely an example of something ultimately rooted in the nervous system, so, yeah.

The stuff about context is more important. A passage won't say that its theme is X thing, and then turn around and throw an example of not-X thing at you. At least not without explicitly marking that thing with "But..." or "Nonetheless..." or whatever.

[RonPurewal]

Also, the passage does not explain the broad definitions of neurologists on Shaker experiment.

The immediately preceding statement about neurologists' interests is sufficient to define this. Don't expect everything to be spelled out for you in incredibly precise detail.

E.g.,
"Clara, who is interested in studying anything people wear or carry besides clothing, defines 'accessories' broadly. Dara, on the other hand, uses the term only to refer to jewelry."
--> Here, it's pretty obvious that Clara defines "anything people wear or carry besides clothing" as an accessory. E.g., Clara would call a purse an "accessory" (although Dara wouldn't).

Same deal.

[Khush]

Hmm. Now i get it.

In #1 there is a very subtle difference between choice B and A, which may be difficult to notice under time pressed condition
(at least for me).

choice A says SHAKER is a behavioral gene = SHAKER is a single gene that controls one behavior

choice B says SHAKER is ONE of the MANY genes that control one behavior= SHAKER is not a single gene doing so = opposite of choice A

[Khush]

I rejected A in #1 as i thought it might be a Trap answer saying so just because the passage says "neurologists"and "ethologists" differ in their opinions on a topic, implying that for any experiment what is a behavioral gene for ethologists will not be the same for neurologists.

Your attitude of suspicion is not unjustified, but you have to remember the context of the passage.
This passage is primarily concerned with the differences between these two groups' conceptions of what makes a gene behavioral. So, if the passage specifically says "This ONE group thinks X", then you should be very strongly slanted toward thinking that the OTHER group thinks... NOT x.

E.g., let's say I'm reading a paragraph about differences between the US and Saudi Arabia.
If the passage mentions that "In the United States, the traditional weekend is Saturday and Sunday", then I should absolutely expect"”and infer"”that the Saudi weekend will fall on different days. If not, then the entire structure of the passage would be completely misleading and/or self-defeating.

In any case, if you need hard proof, it's there.
The passage says that neurologists classify genes as behavioral if they control any behavior generated by the nervous system"”i.e., pretty much anything that an animal ever does.
The shaking is definitely an example of something ultimately rooted in the nervous system, so, yeah.

The stuff about context is more important. A passage won't say that its theme is X thing, and then turn around and throw an example of not-X thing at you. At least not without explicitly marking that thing with "But..." or "Nonetheless..." or whatever.

This is very helpful!

[Khush]

Thank You for all the help Ron!

you Rock!

[RonPurewal]

Hmm. Now i get it.

In #1 there is a very subtle difference between choice B and A, which may be difficult to notice under time pressed condition
(at least for me).

Not a "subtle difference". This difference (single gene vs. multiple genes) is the entirety of choice B.
I.e., choice B is literally concerned with nothing at all, except for whether it's "1 gene" or "more than 1 gene".

If I were to make you read the passage without a goal, then take it away from you, and THEN ask you "one gene, or more than one gene?", then, sure, this would be a valid complaint. But, nope. You still have the passage"”and that's the only issue under consideration in choice B.

Also, you don't even have to find counter-evidence. All you need is the absence of evidence.
Consider this statement: Olivier Rousteing is one of many designers who have influenced my tastes in fashion.
If you wanted to support this statement, then, sure, you'd look for some evidence, somewhere, that Rousteing influenced my tastes. But"”as is probably perfectly clear"”you need to find a mention of some other designer who has done the same. That's your primary search.

Regardless of whether you noticed the words indicating that Shaker controls a certain behavior all by itself, there is very clearly NO evidence of OTHER genes that play a role.
I.e., there is no evidence whatsoever for choice B. None at all.

Don't waste your time looking for counterevidence if there's no evidence in the first place!

[RonPurewal]

choice A says SHAKER is a behavioral gene = SHAKER is a single gene that controls one behavior

The "single gene" thing is not necessary to establish this answer choice. It's enough to notice that it's involved in controlling something that's a function of the nervous system.

More importantly"”see the "Saudi weekend" example above. Even if you have a hard time putting your finger on the specific evidence, this entire passage is structured to draw contrasts between these two groups' definitions of "behavioral gene". So, if (A) were not true, you'd have a passage with no overall unity whatsoever. These passages may be somewhat boring, but they are all well written, so that isn't going to happen.

[Khush]

It could not have been explained better, Ron!

Things are crystal clear now.

Thanks a ton!

[RonPurewal]

You're welcome.