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carcass redskull @crackverbal mikemcgarry Skywalker18

Can you explain question#5.

I got this wrong and cannot figure out still.
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Honestly, this was really tough. Wow. If it was not 800 level it was close, really close.

Thinking during the exam pressure to grasp this passage was surely difficult. I think I needed the five gear :|

Anyhow, after reading it twice I came up that these are clearly wrong.

(D) How do the eyes in flatfish migrate?
(E) How did Parker make his discoveries about the anatomy of optic nerves in flatfish?

Move one

This

(A) Why are Japanese starry flounder mostly left-eyed?

We do know this from the first paragraph is adaptive, that left-eyedness in the Japanese starry flounder has been selected for, . The question is almost an inference from all over the passage. The answer could be anywhere , even in a tiny sentence or a prepositional phrase.

(B) Why should the eye-sidedness in starry flounder be considered selectively neutral?
(C) Why have biologists recently become interested in whether a characteristic is adaptive or selectively neutral?

C is wrong for the following

This situation is one commonly encountered by evolutionary biologists, who must often decide whether a characteristic is adaptive or selectively neutral.

Which means that the question the biologist wonder, basically does not exists. Because they already know. So C is redundant.

B is the answer

As other explanations proved equally untenable, biologists concluded that there is no important adaptive difference between left-eyedness and right-eyedness and that the two characteristics are genetically associated with some other adaptively significant characteristic..

Which means that the fish being neutral is not the only reason. Something else must come in play.

:death:

Regards
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q1 and q5 explaination pls
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q1 and q5 explaination pls

1. According to the passage, starry flounder differ from most other species of flatfish in that starry flounder

On this topic, the passage states, "While in most species with asymmetries virtually all adults share the same asymmetry, members of the starry flounder species can be either left-eyed (both eyes on the left side of head) or right-eyed." In other words, in other species, asymmetries are the same across all individual adults, whereas the starry flounder adults can have different asymmetries.

(A) are not basically bilaterally symmetric All flatfish are asymmetric as per the first sentence of the passage. Eliminate.

(B) do not become asymmetric until adulthood Flatfish (including, presumably, the starry flounder) become asymmetric before maturity ("...before maturity one eye migrates..."). Eliminate.

(C) do not all share the same asymmetry Correct. Consistent with our thinking above.

(D) have both eyes on the same side of the head This is true of all flatfish. Eliminate.

(E) tend to cluster in only certain geographic regions No such information in the passage. Eliminate.

5. The passage supplies information for answering which of the following questions?

(A) Why are Japanese starry flounder mostly left-eyed? This information is not given in the passage. The passage states "As other explanations proved equally untenable, biologists concluded that there is no important adaptive difference between left-eyedness and right-eyedness". Eliminate.

(B) Why should the eye-sidedness in starry flounder be considered selectively neutral? This is explained by the same sentence as mentioned for (A). Correct.Answer.

(C) Why have biologists recently become interested in whether a characteristic is adaptive or selectively neutral? This information is not given in the passage. Eliminate.

(D) How do the eyes in flatfish migrate? This information is not given in the passage - we do not know exactly how the eyes migrate. Eliminate.

(E) How did Parker make his discoveries about the anatomy of optic nerves in flatfish? This information is not given in the passage - we do not know exactly how he made his discoveries. Eliminate.

Hope this helps.
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Took me 11 mins to get 6 out of 7 correct. For question 5 I'm still don't understand why my selection is wrong, would appreciate if anyone can shed some light on.

Reading Note

Paragraph 1: Introduce the term of bilateral symmetry. Flat fish lack it, but most species should share the same asymmetry. However starry flounder don't. Some examples of different proportion at different location.

Paragraph 2: Biologist call it "dine" (or cline? probably a typo here), and think it's adaptive. But question raised regarding what pros it gave starry flounder

Paragraph 3: experiment conducted and mechanism of optic nerve crossing introduced. GH Parker reasoned which side of optic nerve comes on top, it would be selected against. In the case it would be left side not favored

Paragraph 4: however most Japan sf is left eyed. so it shouldn't be naturally selected. no specific reason found, probably "evolutionary red herring"

Question

1. According to the passage, starry flounder differ from most other species of flatfish in that starry flounder

(A) are not basically bilaterally symmetric
(B) do not become asymmetric until adulthood
(C) do not all share the same asymmetry
(D) have both eyes on the same side of the head
(E) tend to cluster in only certain geographic regions

You can find the answer in the first passage "While in most species with asymmetries virtually all adults share the same asymmetry, members of the starry flounder species can be either left-eyed (both eyes on the left side of head) or right-eyed.", so C is the right answer

2. The author would be most likely to agree with which of the following statements about left-eyedness and right-eyedness in the starry flounder?

I. They are adaptive variations by the starry flounder to environmental differences.
II. They do not seem to give obvious selective advantages to the starry flounder.
III. They occur in different proportions in different locations.

(A) I only
(B) II only
(C) I and III only
(D) II and III only
(E) I, II, and III

The last paragraph clearly puts "environmental differences" in question, so I is out.
II coincides with "As other explanations proved equally untenable, biologists concluded that there is no important adaptive difference between left-eyedness and right-eyedness and that the two characteristics are genetically associated with some other adaptively significant characteristic.", keep it
III can be proved with last few sentences in paragraph 1. So answer D is correct


3. According to the passage, a possible disadvantage associated with eye migration in flatfish is that the optic nerves can

(A) adhere to one another
(B) detach from the eyes
(C) cross
(D) stretch
(E) twist

refer to "G. H. Parker reasoned that if, for example, a flatfish's left eye migrated when the right optic nerve was on top, there would be a twisting of nerves, which might be mechanically disadvantageous." in paragraph 2, the answer is E


4. Which of the following best describes the organization of the passage as a whole?

(A) A phenomenon is described and an interpretation presented and rejected.
(B) A generalization is made and supporting evidence is supplied and weighed.
(C) A contradiction is noted and a resolution is suggested and then modified.
(D) A series of observations is presented and explained in terms of the dominant theory.
(E) A hypothesis is introduced and corroborated in the light of new evidence.

The entire paragraph starts with unusual phenomenon, then the 2nd paragraph provides one explanation but with some questions remained, the 3rd develops further with GH Parker's finding, but got contradicted by examples of Japanese sf. The conclusion is that the unusual asymmetry is not a adaption but evolutionary red herring, which means it's not important.

So B, D, E are out because they still think the original "selection" theory is supported
Then between A and C, C mentioned "a resolution is suggested" but the passage didn't introduce any resolution (decision) other than possible explanations. So the correct answer is A


5. The passage supplies information for answering which of the following questions?

(A) Why are Japanese starry flounder mostly left-eyed?
(B) Why should the eye-sidedness in starry flounder be considered selectively neutral?
(C) Why have biologists recently become interested in whether a characteristic is adaptive or selectively neutral?
(D) How do the eyes in flatfish migrate?
(E) How did Parker make his discoveries about the anatomy of optic nerves in flatfish?


The entire passage is trying to figure out why Japanese sf is mostly left-eyed but didn't come up with any solid explanation, so A is out.
"why biologists are interested" is out of scope - C is out
"how did Parker makes the discoveries' is out of scope, E is out
D - I think "In all flatfish, the optic nerves cross, so that the right optic nerve is joined to the brain's left side and vice versa." perfectly explain how do the eyes migrate, what other kinds of info are needed to make a full explanation?



6. Which of the following is most clearly similar to a cline as it is described in the second paragraph of the passage?

(A) A vegetable market in which the various items are grouped according to place of origin
(B) A wheat field in which different varieties of wheat are planted to yield a crop that will bring the maximum profit
(C) A flower stall in which the various species of flowers are arranged according to their price
(D) A housing development in which the length of the front struts supporting the porch of each house increases as houses are built up the hill
(E) A national park in which the ranger stations are placed so as to be inconspicuous, and yet as easily accessible as possible

the "cline" refers to "gradual variation over a certain geographic range". So the correct answer should contain 3 elements - "gradual variation", "geographic range/change" and a hiden one "same species"
A) I don't think this contain either one of the elements, out
B) "different varieties" <> "variation geographically", unless the varieties changed in different locations
C) same flaw as B, out
D) BINGO, we have "increasing length of front struts" and "up the hill", Correct answer
E) same flaw as B and C, out


7. Which of the following phrases from the passage best expresses the author's conclusion about the meaning of the difference between left -eyed and right-eyed flatfish?

(A) "Most striking"
(B) "variation is adaptive"
(C) "mechanically disadvantageous"
(D) "adaptively significant"
(E) "evolutionary red herring"

Pretty straightforward question, refer to the last sentence. Correct answer is E.
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Took me 11 mins to get 6 out of 7 correct. For question 5 I'm still don't understand why my selection is wrong, would appreciate if anyone can shed some light on.

Reading Note

Paragraph 1: Introduce the term of bilateral symmetry. Flat fish lack it, but most species should share the same asymmetry. However starry flounder don't. Some examples of different proportion at different location.

Paragraph 2: Biologist call it "dine" (or cline? probably a typo here), and think it's adaptive. But question raised regarding what pros it gave starry flounder

Paragraph 3: experiment conducted and mechanism of optic nerve crossing introduced. GH Parker reasoned which side of optic nerve comes on top, it would be selected against. In the case it would be left side not favored

Paragraph 4: however most Japan sf is left eyed. so it shouldn't be naturally selected. no specific reason found, probably "evolutionary red herring"

Question

1. According to the passage, starry flounder differ from most other species of flatfish in that starry flounder

(A) are not basically bilaterally symmetric
(B) do not become asymmetric until adulthood
(C) do not all share the same asymmetry
(D) have both eyes on the same side of the head
(E) tend to cluster in only certain geographic regions

You can find the answer in the first passage "While in most species with asymmetries virtually all adults share the same asymmetry, members of the starry flounder species can be either left-eyed (both eyes on the left side of head) or right-eyed.", so C is the right answer

2. The author would be most likely to agree with which of the following statements about left-eyedness and right-eyedness in the starry flounder?

I. They are adaptive variations by the starry flounder to environmental differences.
II. They do not seem to give obvious selective advantages to the starry flounder.
III. They occur in different proportions in different locations.

(A) I only
(B) II only
(C) I and III only
(D) II and III only
(E) I, II, and III

The last paragraph clearly puts "environmental differences" in question, so I is out.
II coincides with "As other explanations proved equally untenable, biologists concluded that there is no important adaptive difference between left-eyedness and right-eyedness and that the two characteristics are genetically associated with some other adaptively significant characteristic.", keep it
III can be proved with last few sentences in paragraph 1. So answer D is correct


3. According to the passage, a possible disadvantage associated with eye migration in flatfish is that the optic nerves can

(A) adhere to one another
(B) detach from the eyes
(C) cross
(D) stretch
(E) twist

refer to "G. H. Parker reasoned that if, for example, a flatfish's left eye migrated when the right optic nerve was on top, there would be a twisting of nerves, which might be mechanically disadvantageous." in paragraph 2, the answer is E


4. Which of the following best describes the organization of the passage as a whole?

(A) A phenomenon is described and an interpretation presented and rejected.
(B) A generalization is made and supporting evidence is supplied and weighed.
(C) A contradiction is noted and a resolution is suggested and then modified.
(D) A series of observations is presented and explained in terms of the dominant theory.
(E) A hypothesis is introduced and corroborated in the light of new evidence.

The entire paragraph starts with unusual phenomenon, then the 2nd paragraph provides one explanation but with some questions remained, the 3rd develops further with GH Parker's finding, but got contradicted by examples of Japanese sf. The conclusion is that the unusual asymmetry is not a adaption but evolutionary red herring, which means it's not important.

So B, D, E are out because they still think the original "selection" theory is supported
Then between A and C, C mentioned "a resolution is suggested" but the passage didn't introduce any resolution (decision) other than possible explanations. So the correct answer is A


5. The passage supplies information for answering which of the following questions?

(A) Why are Japanese starry flounder mostly left-eyed?
(B) Why should the eye-sidedness in starry flounder be considered selectively neutral?
(C) Why have biologists recently become interested in whether a characteristic is adaptive or selectively neutral?
(D) How do the eyes in flatfish migrate?
(E) How did Parker make his discoveries about the anatomy of optic nerves in flatfish?


The entire passage is trying to figure out why Japanese sf is mostly left-eyed but didn't come up with any solid explanation, so A is out.
"why biologists are interested" is out of scope - C is out
"how did Parker makes the discoveries' is out of scope, E is out
D - I think "In all flatfish, the optic nerves cross, so that the right optic nerve is joined to the brain's left side and vice versa." perfectly explain how do the eyes migrate, what other kinds of info are needed to make a full explanation?



6. Which of the following is most clearly similar to a cline as it is described in the second paragraph of the passage?

(A) A vegetable market in which the various items are grouped according to place of origin
(B) A wheat field in which different varieties of wheat are planted to yield a crop that will bring the maximum profit
(C) A flower stall in which the various species of flowers are arranged according to their price
(D) A housing development in which the length of the front struts supporting the porch of each house increases as houses are built up the hill
(E) A national park in which the ranger stations are placed so as to be inconspicuous, and yet as easily accessible as possible

the "cline" refers to "gradual variation over a certain geographic range". So the correct answer should contain 3 elements - "gradual variation", "geographic range/change" and a hiden one "same species"
A) I don't think this contain either one of the elements, out
B) "different varieties" <> "variation geographically", unless the varieties changed in different locations
C) same flaw as B, out
D) BINGO, we have "increasing length of front struts" and "up the hill", Correct answer
E) same flaw as B and C, out


7. Which of the following phrases from the passage best expresses the author's conclusion about the meaning of the difference between left -eyed and right-eyed flatfish?

(A) "Most striking"
(B) "variation is adaptive"
(C) "mechanically disadvantageous"
(D) "adaptively significant"
(E) "evolutionary red herring"

Pretty straightforward question, refer to the last sentence. Correct answer is E.

For Q6, the passage you have quoted - hasn't that theory been rejected? So actually it is still unanswered?
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PhantomAY
Took me 11 mins to get 6 out of 7 correct. For question 5 I'm still don't understand why my selection is wrong, would appreciate if anyone can shed some light on.

....

For Q6, the passage you have quoted - hasn't that theory been rejected? So actually it is still unanswered?

Good question - the rejection is on the fact that flatfish's eye placement is not a result of response to environmental differences (the cause), not on the term "cline" itself which ONLY describes the phenomenon - "gradual variation over a certain geographic range".
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PhantomAY
Took me 11 mins to get 6 out of 7 correct. For question 5 I'm still don't understand why my selection is wrong, would appreciate if anyone can shed some light on.

....

For Q6, the passage you have quoted - hasn't that theory been rejected? So actually it is still unanswered?

Good question - the rejection is on the fact that flatfish's eye placement is not a result of response to environmental differences (the cause), not on the term "cline" itself which ONLY describes the phenomenon - "gradual variation over a certain geographic range".

I'm sorry, I meant Q5, for which you still don't get why B is incorrect.
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PhantomAY
Took me 11 mins to get 6 out of 7 correct. For question 5 I'm still don't understand why my selection is wrong, would appreciate if anyone can shed some light on.

....

For Q6, the passage you have quoted - hasn't that theory been rejected? So actually it is still unanswered?

Good question - the rejection is on the fact that flatfish's eye placement is not a result of response to environmental differences (the cause), not on the term "cline" itself which ONLY describes the phenomenon - "gradual variation over a certain geographic range".

I'm sorry, I meant Q5, for which you still don't get why B is incorrect.

I assume you mean D? B is correct for "This situation is one commonly encountered by evolutionary biologists, who must often decide whether a characteristic is adaptive or selectively neutral.", given "adaptive" is rejected "selectively neutral" is the only cause.

For D) How do the eyes in flatfish migrate?, I assume it ask for the mechanism behind eye migration (like how you fix your car, not "why you have to fix your car"). The cause "being adaptive" (why you have to fix car) was rejected for sure, but the info presented still explains the mechanism of eye migration - optic nerve crossing (how you fix your car). Does that make sense to you?
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PhantomAY
Took me 11 mins to get 6 out of 7 correct. For question 5 I'm still don't understand why my selection is wrong, would appreciate if anyone can shed some light on.

....

For Q6, the passage you have quoted - hasn't that theory been rejected? So actually it is still unanswered?

Good question - the rejection is on the fact that flatfish's eye placement is not a result of response to environmental differences (the cause), not on the term "cline" itself which ONLY describes the phenomenon - "gradual variation over a certain geographic range".

I'm sorry, I meant Q5, for which you still don't get why B is incorrect.

I assume you mean D? B is correct for "This situation is one commonly encountered by evolutionary biologists, who must often decide whether a characteristic is adaptive or selectively neutral.", given "adaptive" is rejected "selectively neutral" is the only cause.

For D) How do the eyes in flatfish migrate?, I assume it ask for the mechanism behind eye migration (like how you fix your car, not "why you have to fix your car"). The cause "being adaptive" (why you have to fix car) was rejected for sure, but the info presented still explains the mechanism of eye migration - optic nerve crossing (how you fix your car). Does that make sense to you?

But if the 'optic nerve crossing' part is true -> it would also mean that it leads to twisting of nerves -> mechanically disadvantageous.
However, we know that that is not true. Hence I don't think option D has been answered in the passage.
That's how i ruled out D.
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livfcind

For Q6, the passage you have quoted - hasn't that theory been rejected? So actually it is still unanswered?

Good question - the rejection is on the fact that flatfish's eye placement is not a result of response to environmental differences (the cause), not on the term "cline" itself which ONLY describes the phenomenon - "gradual variation over a certain geographic range".

I'm sorry, I meant Q5, for which you still don't get why B is incorrect.

I assume you mean D? B is correct for "This situation is one commonly encountered by evolutionary biologists, who must often decide whether a characteristic is adaptive or selectively neutral.", given "adaptive" is rejected "selectively neutral" is the only cause.

For D) How do the eyes in flatfish migrate?, I assume it ask for the mechanism behind eye migration (like how you fix your car, not "why you have to fix your car"). The cause "being adaptive" (why you have to fix car) was rejected for sure, but the info presented still explains the mechanism of eye migration - optic nerve crossing (how you fix your car). Does that make sense to you?

But if the 'optic nerve crossing' part is true -> it would also mean that it leads to twisting of nerves -> mechanically disadvantageous.
However, we know that that is not true. Hence I don't think option D has been answered in the passage.
That's how i ruled out D.

I appreciate the discussion here livfcind! :)

"In all flatfish, the optic nerves cross, so that the right optic nerve is joined to the brain's left side and vice versa. This crossing introduces an asymmetry, as one optic nerve must cross above or below the other. G. H. Parker reasoned that if, for example, a flatfish's left eye migrated when the right optic nerve was on top, there would be a twisting of nerves, which might be mechanically disadvantageous. For starry flounders, then, the left-eyed variety would be selected against, since in a starry flounder the left optic nerve is uppermost."

To my understanding, above highlighted in BLUE session is given as facts while the red session is Parker's interpretation of the blue session. He argued that because the right optic nerve was on the top, eye migration should favor the right. This understanding has been rejected by last Paragraph by citing the Japanese case. But it didn't attack the premise (optic nerve crossing) but the conclusion of Parker reasoning it should favor right eye migration.

The mechanism should be the same, the differences are just how people interpret it. Or maybe I'm reading too much into it...
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All correct in 13 minutes. Tough passage that tests close reading. It's better to spend an additional minute reading the passage closely than going faster and missing key details that are important in order to answer these questions.

Took 5 minutes to read, although a bit more than suggested, taking that additional time helped me fully grasp everything and answer all correctly
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