Nearly a century ago, biologists found that if they separated an inver

As per Q3, According to the passage, when biologists believed that the cells in the early embryo were undetermined, they made which of the following mistakes?
(A) They did not attempt to replicate the original experiment of separating an embryo into two parts.
(B) They did not realize that there was a connection between the issue of cell determination and the outcome of the separation experiment.
(C) They assumed that the results of experiments on embryos did not depend on the particular animal species used for such experiments.
(D) They assumed that it was crucial to perform the separation experiment at an early stage in the embryo’s life.
(E) They assumed that different ways of separating an embryo into two parts would be equivalent as far as the fate of the two parts was concerned.

As mentioned in the 1st para, especially these sentence "Later biologists found that the situation was not so simple. It matters in which plane the embryo is cut. If it is cut in a plane different from the one used by the early investigators, it will not form two whole embryos.", the problem is that the biologists use result of a particular case to emphasize generalization for all cases. They did not consider what will happen if the cut is made in a different plane (different ways of separating an embryo.......). That's why (E) is correct.

All other options cannot be inferred from the passage.

Can anyone explain question 1?.
Where is it mentioned remotely about the quantity of morphogenetic determinants?
Is the logic this :- an embryo can be separated to form two separate individual embryos and so morpho-determinants are subsequently used for tow embryos instead of one?

Yes, that's the correct logic! Although the "substances that function as morphogenetic determinants" are not evenly distributed, when the fertilized egg splits, at least some of the substances will go to each of the two new embryos if both are to "survive and develop as two normal embryos". If an early embryo only contained the exact quantity necessary for development, it would be impossible for the embryo to split and develop as two normal embryos.
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Hi, can anybody explain me how Maternal Messenger RNA's are considered the morpho determinants?

Hi,

Just read the 2nd paragraph and the beginning of the 3rd paragraph, then you're gonna see why

"Studying sea urchins, biologist Paul Gross found that an unfertilized egg contains substances that function as morphogenetic determinants. They are located in the cytoplasm of the egg cell; i.e., in that part of the cell’s protoplasm that lies outside of the nucleus. In the unfertilized egg, the substances are inactive and are not distributed homogeneously. When the egg is fertilized, the substances become active and, presumably, govern the behavior of the genes they interact with. Since the substances are unevenly distributed in the egg, when the fertilized egg divides, the resulting cells are different from the start and so can be qualitatively different in their own gene activity.
The substances that Gross studied are maternal messenger RNA’s—products of certain of the maternal genes"

Hope this helps.

GMATNinja,

How are we supposed to determine who the target audience is for this paper? I have never come across a question like this, and I find the answer perplexing. This could have been directed at any audience.

My gripe with the answer E is that we are forced to assume these students are not freshmen with a high school level background.

Any help on this would be greatly appreciated!
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It is taken from this article.

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why not option D in this case (question 1) ...

Would option D cater to folks who want to learn about "new species" ...this too me sounds like new embroyos

If you've ever read a published scientific study you'll know that scientist to scientist communication is typically written in a way that is all but incomprehensible to the layman. This passage is clearly educational in nature and the overview of the topic given is overly broad for an audience that would already be familiar with it. If the intended audience were molecular biologists there would be no need to explain what a morphogenetic determinant is for example, because that audience would already know.

RonPurewal , GMATNinja could you please advise how to approach such passages. I got only three right even though I read it very carefully.

ravikumarmishra, if you haven't already, check out the Ultimate RC Guide for Beginners, and try applying those concepts to this passage (i.e. reading for structure and purpose).

If you have any specific questions, feel free to use the request verbal experts' reply button.

Good luck!
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VeritasPrepKarishma,
Could you please explain Q6 and the choices.

Anyone else find this passage very difficult? Where can I find explanations to all the questions?

I got 4(Q-1,2,5,6) wrong and the worst thing about that is that it took me 23 min.

Q1 - Took POE approach. Thought that B is the answer believing that it is an article may have been published in Science journal. Straight forward eliminating A and D, can't ne alumni because then Paul Gross must have been mentioned in the first paragraph itself. Coming down to B and E, i eliminated the later overthinking that undergraduate course can't have such debate with historical significance mention(Forgive me for my non-medical background).

Q2 - Here again POE approach. Few i rejected based on key words in the five points. B & D eliminated based on 'evenly' and 'identical' keywords respecively. Option-A was wrong because of wrong location issue. Option-E i rejected thinking(overthinking) that 'MD quantities' is nowhere mentioned ATLEAST for single individual. Had it been Two individuals i might have stopped and paid more attention to this one. Lastly, chose C for that i could find 'inactivity' and 'irreversibly committed' in the passage. I thought MD is inactive and becomes irreversibly committed which is right but overseeing that that Option-C talks about embryo cells becoming irreversibly committed instead.

Q5 - C & E can't be established through passage hence eliminated. Then rejected D and just chose B with a hunch that that the choice is wrong after several readings(which were of no help though). Had a hunch that A is correct as mentioned in Para-3.

Q6 - Eliminated C & E straight. After that chose D overseeing and mismatching the facts. But since about this Q i had no idea i didn't pay much attention and went with C.

Have been following QOTDs regularly but not posting my responses. The reason being that i get on an average 5-6 right out of 7,8 & 9 Q's and there has been no improvement either i spend 16 minutes for 8-9 Q's or 23-24 minutes. For the previous QOTD i got 6 correct out of 8 in 21 minutes and 5 out of 7 right for before that.

PS: My RC and CR are weakest, SC-can say a little improved, trying to improve my verbal overall.
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Hi,

RonPurewal , GMATNinja

Could somebody please let me know the source of the passage ? Is it from one of the Tests of Manhattan/Veritas/E-Gmat/Kaplan etc ?

Regards

That was a tough one for me too. It was mostly a POE for me. I thought it was either a science expert or a rookie scientist. In the end, I picked the correct choice.

Can somebody please explain the answer for Question no. 9. I was able to eliminate B, C and E, but was confused between A and E.

Assuming you were confused between A and D (not A and E) on question 9, let’s take a look at the debate described in the passage:


Biologists reach an impasse in their debate over the origins of the embryo phenomenon because “no one was able to ask crucial questions in a form in which they could be pursued.” In other words, they were unable to formulate questions in a way that could be answered.

With that in mind, we can consider which answer choice presents circumstances most similar to those faced by the biologists:


Although such a literary scholar may struggle to understand original source materials in an unfamiliar language, there are presumably others that understand the language and could assist the literary scholar. Unlike the biologists in the passage, the literary scholar would have much needed aid from other experts. Furthermore, the literary scholar would almost certainly be capable of formulating his questions about the source material in a way that could be answered. Eliminate (A).

And here’s (D):


Much like the biologists who knew little about the fundamentals of embryos, the linguist in (D) knows little about the fundamentals of the language he/she is studying. For that reason, the linguist is unlikely to be able to formulate questions about language acquisition that can be answered. (D) is the correct answer for question 9.

I hope that helps!
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Can anyone explain me Question 1

I am confused between option B and E.

How to eliminate B?