Due in large part to agricultural runoff and pollutants from industria

Question

Due in large part to agricultural runoff and pollutants from industrial wastewater, increasingly large areas of the ocean are being pronounced irreparably hypoxic, a condition that poses serious threats to marine species that require abundant oxygen to survive. Some fish may be able to tolerate this environment, and some species are more successful than others at escaping from these "dead zones." But they escape to unfamiliar habitats where they are less capable of defending themselves against predators and are less likely to be fertile. The infertility is linked directly to the lack of oxygen in the environment from which they escaped; this lack appears to wreak the most havoc on the female members of the species.

The threat of hypoxic zones to the marine ecosystem has been known for some time, but recent research has revealed an additional threat that increases the likelihood of species extinction. It appears that low levels of dissolved oxygen inhibit the function of genes that control gender specificity in some fish, which means that the hypoxic water can induce sex changes in certain species. This causes an overabundance of males and reduces their opportunities to reproduce. Furthermore, the hypoxic waters compromise the quantity and quality of the female eggs. The females that do survive their deadly habitat may therefore either be functionally infertile or may produce offspring that are biologically ill equipped to contribute to population growth and help ensure survival of the species.    1 
 1. The author's primary objective in discussing hypoxic zones is to explain how they

A. compromise the health of marine ecosystems.
B. contribute to the extinction of certain marine life.
C. alter the chemical composition of ocean habitats.
D. have been linked to altered gene expression in fish.
E. are depleted of oxygen over long periods of time.

2 
 2. The passage implies that fish that can survive in hypoxic zones

A. have developed a tolerance for anoxia as the species evolved.
B. belong to species that are indigenous to less oxygenated areas of the ocean.
C. suffer damage that is more apparent in their offspring than in themselves.
D. must move to healthier waters in order to reproduce.
E. rely on a biological self-defense mechanism to compensate for the oxygen depletion.

3 
 3. The first paragraph primarily performs which of the following functions in the passage?

A. It links compositional changes in ocean water to irresponsible human behavior.
B. It explains how environmental damage can cause effects that last for generations.
C. It stresses that oxygen levels are paramount in determining ocean survival rates.
D. It pinpoints the cause of species destruction in specific marine habitats.
E. It argues that survival in the changing ocean depends on genetic factors.

Pankaj0901 · Answer

Answer:
1. A
2. C
3. A

1. The author's primary objective in discussing hypoxic zones is to explain how they

A. compromise the health of marine ecosystems.
B. contribute to the extinction of certain marine life.
C. alter the chemical composition of ocean habitats.
D. have been linked to altered gene expression in fish.
E. are depleted of oxygen over long periods of time.

Answer A. The author describes how hypoxic zones affect the health of marine ecosystems.

2. The passage implies that fish that can survive in hypoxic zones

A. have developed a tolerance for anoxia as the species evolved.
B. belong to species that are indigenous to less oxygenated areas of the ocean.
C. suffer damage that is more apparent in their offspring than in themselves.
D. must move to healthier waters in order to reproduce.
E. rely on a biological self-defense mechanism to compensate for the oxygen depletion.

Answer C. It is evident from the 2nd paragraph: "The females that do survive their deadly habitat may therefore either be functionally infertile or may produce offspring that are biologically ill equipped to contribute to population growth and help ensure survival of the species."

3. The first paragraph primarily performs which of the following functions in the passage?

A. It links compositional changes in ocean water to irresponsible human behavior.
B. It explains how environmental damage can cause effects that last for generations.
C. It stresses that oxygen levels are paramount in determining ocean survival rates.
D. It pinpoints the cause of species destruction in specific marine habitats.
E. It argues that survival in the changing ocean depends on genetic factors.

Answer A. It is evident from the first line that human behavior leads to compositional changes in ocean water.

ash124 · Answer

Understand the passage: 
 Para1:
Due to pollution, increasingly large areas of the ocean are being pronounced irreparably hypoxic, a condition that poses serious threats to marine species that require abundant oxygen to survive, and It affects on marine life
Para2:
the additional threat that increases the likelihood of species extinction

1. The author's primary objective in discussing hypoxic zones is to explain how they

A. compromise the health of marine ecosystems.
 the hypoxic zone is the resulting effect due to pollution  
 I have an issue with the ecosystem as it can contain many things apart  
B. contribute to the extinction of certain marine life.
 It does talk about extinction 
C. alter the chemical composition of ocean habitats.
 not the main objective. 
D. have been linked to altered gene expression in fish.
 not the primary objective 
E. are depleted of oxygen over long periods of time.
 not discussed

Answer B

2. The passage implies that fish that can survive in hypoxic zones

A. have developed a tolerance for anoxia as the species evolved.
 nothing related to evolution. 
B. belong to species that are indigenous to less oxygenated areas of the ocean.
 We don't know about "indigenous" 
C. suffer damage that is more apparent in their offspring than in themselves.
 Yes, it is given in 2nd para. 
D. must move to healthier waters in order to reproduce.
 not given 
E. rely on a biological self-defense mechanism to compensate for the oxygen depletion.
 not given

Answer C

3. The first paragraph primarily performs which of the following functions in the passage?

A. It links compositional changes in ocean water to irresponsible human behavior.
 It does 
B. It explains how environmental damage can cause effects that last for generations.
 "Generation" comes in 2nd para. 
C. It stresses that oxygen levels are paramount in determining ocean survival rates.
 Nothing about "paramount" 
D. It pinpoints the cause of species destruction in specific marine habitats.
 It does talk about dead zones but not any specific marine habitats 
E. It argues that survival in the changing ocean depends on genetic factors.
 Not given

Answer A

RohitSaluja · Answer

Wow, the shorter the passage the harder it is :p. Let me try to take a stab at it

Q1. The author's primary objective in discussing hypoxic zones is to explain how they - Answer D

A. compromise the health of marine ecosystems. - Although I selected A while answering the question, during typing I realized this can't be the answer, as the first line of the second paragraph states "The threat of hypoxic zones to the marine ecosystem has been known for some time". So everyone knows about the threat and then author goes on to explain the recent research that talks about how it alters the genes of fish. So D is the correct answer

B. contribute to the extinction of certain marine life. - The passage does mention that the "likelihood of species extinction" is increased but that does not necessarily means that it will contribute to it, hence out

C. alter the chemical composition of ocean habitats. - Nowhere in the passage chemical composition is discussed

D. have been linked to altered gene expression in fish. - Correct answer choice for the reason mentioned above

E. are depleted of oxygen over long periods of time. - Not mentioned

Q2. The passage implies that fish that can survive in hypoxic zones - Answer C

Only option C fits the puzzle and is directly mentioned in the passage

A. have developed a tolerance for anoxia as the species evolved. - Never mentioned in the passage
B. belong to species that are indigenous to less oxygenated areas of the ocean. - Never mentioned in the passage 
C. suffer damage that is more apparent in their offspring than in themselves. - Mention in the second paragraph "may produce offspring that are biologically ill equipped"
D. must move to healthier waters in order to reproduce. - Never mentioned in the passage 
E. rely on a biological self-defense mechanism to compensate for the oxygen depletion. - Never mentioned in the passage

Q3. The first paragraph primarily performs which of the following functions in the passage? - Answer B

Given the passage talks about the impact of low levels of O2 on the fertility, option B is the correct answer choice

A. It links compositional changes in ocean water to irresponsible human behavior.
B. It explains how environmental damage can cause effects that last for generations.
C. It stresses that oxygen levels are paramount in determining ocean survival rates.
D. It pinpoints the cause of species destruction in specific marine habitats.
E. It argues that survival in the changing ocean depends on genetic factors.

SomeOneUnique · Answer

According to the best of my ability, kindly find the answers here.

1. The author's primary objective in discussing hypoxic zones is to explain how they

A. compromise the health of marine ecosystems. => I do not find a health check as such in the passage.  INCORRECT 
B. contribute to the extinction of certain marine life. => Para 2 line 1 mentions 'likelihood of species extinction' to explain how some species are escaping and some are tolerating them and all that leads to extinction.  CORRECT 
C. alter the chemical composition of ocean habitats. => chemical composition is not mentioned  INCORRECT 
D. have been linked to altered gene expression in fish. => It is true but that is not the primary reason to discuss the zones.  INCORRECT 
E. are depleted of oxygen over long periods of time. => Para 1 line 1 says 'agricultural runoff and pollutants' causes hypoxic zones but it does not mention that these results are  recent  or over long periods of time.  INCORRECT

2. The passage implies that fish that can survive in hypoxic zones

EXPLANATION: The passage mentions certain handicaps for the fishes that survive these zones (mentioned in para 2 line 2, line 3, line 4) - sex changes in certain species, overabundance of males, reduces their opportunities to reproduce, functionally infertile female or biologically ill offspring. Thus it might be advisable to move to  
A. have developed a tolerance for anoxia as the species evolved. => Para 1 line 1 talks about hypoxia (lack of xygen) but not anoxia (no oxygen). Also nothing is said about species evolution in a positive way.  INCORRECT 
B. belong to species that are indigenous to less oxygenated areas of the ocean. => Para 1 line 2 mentions 'Some fish may be able to tolerate this environment and some species are successful at escaping from these "dead zones."' which implies - the fishes that can tolerate now live their but we do not know earlier where they lived, hence not indigenous.  INCORRECT 
C. suffer damage that is more apparent in their offspring than in themselves. => female fish become infertile but their kids are sometimes not born and sometimes born with the inability to reproduce.  CORRECT 
D. must move to healthier waters in order to reproduce. => Para 1 line 3 mentions - 'species that escape are less likely to be fertile'. Thus moving to healthier water does not guarantee reproduction. fertility.  INCORRECT 
E. rely on a biological self-defense mechanism to compensate for the oxygen depletion. => self defense is not mentioned in passage.  INCORRECT

3. The first paragraph primarily performs which of the following functions in the passage?

EXPLANATION: Para 1 introduces problems of marine ecosystem due to agricultural runoff and pollutants from industrial wastewater. 
A. It links compositional changes in ocean water to irresponsible human behavior. => It links human behavior, correct. But link to composition of water ? (Water everywhere is H2O. - I know I am bringing outside knowledge but it is to highlight the incorrectness of word composition.) Also, human behavior is linked to something more serious. It lead to something more serious - (first line)  irreparably hypoxic , a condition that poses  serious threats to marine species .  INCORRECT 
B. It explains how environmental damage can cause effects that last for generations. => In the name of generations, offspring is mentioned but in para 2 not in para 1 last line.  INCORRECT 
C. It stresses that oxygen levels are paramount in determining ocean survival rates. => Oxygen levels make changes in marine ecosystem but it does not decide survival rate. INCORRECT 
D. It pinpoints the cause of species destruction in specific marine habitats. => There are many adverse effects and it seems right to say 'pinpoint' the cause of specie destruction.  CORRECT 
E. It argues that survival in the changing ocean depends on genetic factors. => Passage does not bring genetic history with respect to survival.  INCORRECT

Gaudapada · Answer

1. The author's primary objective in discussing hypoxic zones is to explain how they

A. compromise the health of marine ecosystems.  
Author mentions in the first line of  paragraph 2  that the threat to the health of marine ecosystem has been known for a while. Author then talks about an additional threat revealed by recent research. Hence  A  cannot be the primary objective.

B. contribute to the extinction of certain marine life.  
 CORRECT :   In  paragraph 2  the author mentions how hypoxic zones lead to infertility in certain species of fish which could lead to their extinction.

C. alter the chemical composition of ocean habitats.  
This is mentioned but it's not the primary objective of the author in bringing up hypoxic zones. No mechanism of altering the chemical composition of oceans is provided. It is mentioned as a fact which leads to a conclusion (hypoxic zones could cause extinction of certain species) , not the conclusion itself.

D. have been linked to altered gene expression in fish.  
Author is not mentioning the mechanism for altered gene expression in fish. Hence it is not the primary objective. It is a supporting point towards the main conclusion.

E. are depleted of oxygen over long periods of time.  
As with  C  and  D ,this is not the main objective. It is a fact about hypoxic zones.

2. The passage implies that fish that can survive in hypoxic zones

A. have developed a tolerance for anoxia as the species evolved.  
If a tolerance was developed, the fish would not be affected so badly. From  paragraph 2  we can conclude that no such evolution has taken place.

B. belong to species that are indigenous to less oxygenated areas of the ocean.  
Passage never mentions that fish surviving in hypoxic zones migrated from other less oxygenated areas.

C. suffer damage that is more apparent in their offspring than in themselves.  
 CORRECT :   Although the fish are able to survive in hypoxic zones, research reveals significant damage to their offspring. From  paragraph 2 , 
 "Furthermore, the hypoxic waters compromise the quantity and quality of the female eggs. The females that do survive their deadly habitat may therefore either be functionally infertile or may produce offspring that are biologically ill equipped to contribute to population growth and help ensure survival of the species." . Hence  C  is correct

D. must move to healthier waters in order to reproduce.  
 paragraph 2  mentions fish that live and reproduce in the hypoxic zones. It is never implied that the fish  MUST  move to healthier waters to reproduce.

E. rely on a biological self-defense mechanism to compensate for the oxygen depletion.  
There is no implicit or explicit mention of any self-defense mechanism that the fish employ.

3. The first paragraph primarily performs which of the following functions in the passage?

A. It links compositional changes in ocean water to irresponsible human behavior.  
Irresponsible human behavior is mentioned in  paragraph 1  but does not serve as the primary function of the paragraph. It is just the introduction. Author never expounds on this link after the first sentence.

B. It explains how environmental damage can cause effects that last for generations.  
Environmental damage is too vague. The passage deals with a specific type of environmental damage, not environmental damage as a whole.

C. It stresses that oxygen levels are paramount in determining ocean survival rates.  
Harmful effects of low oxygen levels is mentioned but author never says the oxygen levels are the  most important factor  in determining survival rates.

D. It pinpoints the cause of species destruction in specific marine habitats.  
 CORRECT :   Author pinpoints the cause ( increasingly large areas of the ocean becoming hypoxic due to industrial waste) and details the destruction of certain species in affected habitats due to said cause.

E. It argues that survival in the changing ocean depends on genetic factors.  
Author makes no such argument. We could say that the environmental pressures could favor certain genetic traits but this is an extrapolation, and is not stated in the passage.

sahiba96 · Answer

1. The author's primary objective in discussing hypoxic zones is to explain how they

A.  compromise the health of marine ecosystems.   
 B. contribute to the extinction of certain marine life.  
in second parah the author mentions : 
The threat of  hypoxic zones  to the marine ecosystem has been known for some time, but recent research has revealed an additional threat that increases the likelihood of species  extinction 
explaining how these zones are contributing to extinction 
 C. alter the chemical composition of ocean habitats.
D. have been linked to altered gene expression in fish.
E. are depleted of oxygen over long periods of time.

2. The passage implies that fish that can survive in hypoxic zones

A. have developed a tolerance for anoxia as the species evolved. 
 B. belong to species that are indigenous to less oxygenated areas of the ocean.  
this line stated in first paragh : a condition that poses serious threats to marine species that require abundant oxygen to survive. Some fish may be able to tolerate this environment 
i.e., those species that are able to survive do not require as much oxygen as other species do. 
 C. suffer damage that is more apparent in their offspring than in themselves.   
 no comparision is made between offsprnings and species  
 D. must move to healthier waters in order to reproduce.   no such thing is stated  
 E. rely on a biological self-defense mechanism to compensate for the oxygen depletion.
  no such thing about self defense is stated

3. The first paragraph primarily performs which of the following functions in the passage?

A. It links compositional changes in ocean water to irresponsible human behavior.  
 B. It explains how environmental damage can cause effects that last for generations.  1st para talks about how the hypoxic areas cause some species escape to other habitats and eventually become less fertile. i.e an effect that will impact many generations. 
 C. It stresses that oxygen levels are paramount in determining ocean survival rates.  
 D. It pinpoints the cause of species destruction in specific marine habitats.  
 E. It argues that survival in the changing ocean depends on genetic factors.

c93liu · Answer

Q1 - my answer is A)

It is a tough debate between A) and B), but I picked A) ultimately because of the following:
1) While certain parts of the passage are clearly talking about extinction risks posed by hypoxic zones, the main objective seems to link the threat of extinction of certain species to the overall damage to the marine ecosystem. Choice B) makes it too narrow of a focus and missing the whole picture; 2) Specifically at the beginning of paragraph 2, the passage talks about "the threat of H zones to the marine ecosystem", which summarizes paragraph 1 and functions as a transition to additional threats to be discussed.

A) - See the discussions above.
B) - See the discussions above.
C) - This is not discussed in the passage. H zone is caused by an irreparable depletion of oxygen (alter the chemical composition), but this is not the main goal of discussing H zones.
D) - This is a very narrow aspect of one of the direct outcomes of H zones discussed near the end of paragraph 2 but not the main objective.
E) - "over long periods of time" is not discussed.

Q2 - my answer is C)

The entire 2nd paragraph is dedicated to the damage of H zones to the fish species that survive in them (1st paragraph talks about fish species that escape from the H zone).

A) - Anoxia means an absence of oxygen, which is a more severe form of hypoxia. So this option is too extreme.
B) - Whether the species is indigenous to H zones or evolved over time to tolerate low levels of oxygen and migrated to the H zones is not discussed.
C) - Yes, both the induced sex change and the compromised quantity and quality of female eggs make this option true (that damage is more apparent in offspring).
D) - This is not discussed in the passage.
E) - We do not know how they tolerate low levels of oxygen.

Q3 - my answer is B)

The primary function of the 1st paragraph is to discuss how H zones cause damages to fish species that escape them.

A) - Although this is discussed, it is only at the intro sentence to the paragraph and certainly not the main function.
B) - Yes, the long-term effect / damage (infertility in female members of the fish species) is the primary function.
C) - We know that oxygen level is one important aspect. We do not know if it is paramount.
D) - Paragraph 1 mainly deals with the cause -> effect of H zones. According to D), paragraph 1 would be effect -> cause, the exact opposite.
E) - This is not discussed at all in the 1st paragraph.

snscatter · Answer

1. The author's primary objective in discussing hypoxic zones is to explain how they

A. compromise the health of marine ecosystems. –  No. Although this is present in the passage but author has a more specific objective as given in Option B 
B. contribute to the extinction of certain marine life. –  Yes, refer to line “The threat of hypoxic zones to the marine ecosystem has been known for some time, but recent research has revealed an additional threat that increases the likelihood of species extinction.” 
C. alter the chemical composition of ocean habitats. –  No, we only know about lack of O2 and nothing else 
D. have been linked to altered gene expression in fish. -  No. Although this is present in the passage but author has a more specific objective as given in Option B 
E. are depleted of oxygen over long periods of time. –  No. Can’t refer this from the passage

2. The passage implies that fish that can survive in hypoxic zones

A. have developed a tolerance for anoxia as the species evolved. –  No, can’t refer that from the passage 
B. belong to species that are indigenous to less oxygenated areas of the ocean. –  Yes, refer to line “a condition that poses serious threats to marine species that require abundant oxygen to survive.” So fishes that can survive probably don’t require abundant oxygen to survive 
C. suffer damage that is more apparent in their offspring than in themselves.-  No, refer to line “The females that do survive their deadly habitat may therefore either be functionally infertile or may produce offspring that are biologically ill equipped to contribute to population growth and help ensure survival of the species.”  
D. must move to healthier waters in order to reproduce. –  No, that is not necessarily true. Refer to above mentioned line from passage. 
E. rely on a biological self-defense mechanism to compensate for the oxygen depletion. –  No, can’t refer that from the passage

3. The first paragraph primarily performs which of the following functions in the passage?

A. It links compositional changes in ocean water to irresponsible human behavior. –  Yes, that is what the first paragraph does 
B. It explains how environmental damage can cause effects that last for generations. –  No, can cause effects to who? Environmental damage or ocean damage? 
C. It stresses that oxygen levels are paramount in determining ocean survival rates. –  No, it does not stress that. Passage talks about survival of marine species and not the ocean itself. 
D. It pinpoints the cause of species destruction in specific marine habitats. –  No, the passage does not pinpoint that. It generally talks about how hypoxic ocean can affect the marine life.  
E. It argues that survival in the changing ocean depends on genetic factors. –  No. Although it does mention that “Some fish may be able to tolerate this environment” which means these species must have some genetic factors that allow them to stay in such environment but that is not the heart of the passage

Sellby · Answer

The first paragraph intends to explain some serious threats faced by certain marine species and to link those impacts to certain human practices. It seems to explain the threats to emphasize the severity of such impacts caused directly by certain practices.
The second paragraph introduces a new finding that reveals even more serious impact of the human practices than what had been known so far. It goes on the explain the threat in order to underscore the seriousness of the situation.

Question 1:
1. The author's primary objective in discussing hypoxic zones is to explain how they

A. compromise the health of marine ecosystems.
The author doesn't talk about health marine ecosystem in general but addresses the cases in which hypoxic zones affect certain species especially fish species.

B. contribute to the extinction of certain marine life. 
As discussed above, this should be the one.

C. alter the chemical composition of ocean habitats.
Even though we can infer/assume so, this is not the "primary objective". The focus is on how hypoxic zone leads to extinction.

D. have been linked to altered gene expression in fish.
Again, though we can infer/assume so, this is not the "primary objective". Nevertheless, "gene inhibition" is what the author stated but "gene alteration" is nowhere mentioned.

E. are depleted of oxygen over long periods of time.
Apart from the fact that there's no hint about "long periods of time", long time is not the focus of the passage.

Question 2:
2. The passage implies that fish that can survive in hypoxic zones

A. have developed a tolerance for anoxia as the species evolved.
Anoxia is nowhere mentioned/implied in the passage.

B. belong to species that are indigenous to less oxygenated areas of the ocean.
Indigeneity of the impacted species is never talked about

C. suffer damage that is more apparent in their offspring than in themselves. 
Yes, the second para talks about the impact on gender specificity, fertility & sexuality of the offspring even though their parents, which were able to tolerate and survive in "dead zones", could reproduce successfully. Note that this question specifically asks about those  survive  in dead zone, not the ones escape dead zones.

D. must move to healthier waters in order to reproduce.
Though it's stated that some fish species move to healthier waters, "must move to reproduce" is meant nowhere. The second para even talks about species reproducing in the "dead zone" itself.

E. rely on a biological self-defense mechanism to compensate for the oxygen depletion.
Again, "a biological self-defense mechanism" is nowhere implied in the passage.

Question 3:
3. The first paragraph primarily performs which of the following functions in the passage?
As discussed in the beginning, while the first para mentions/implies some of the options given below, the function of the para, in entirety, is to explain some serious threats faced by certain marine species and link those impacts to certain human practices.

A. It links compositional changes in ocean water to irresponsible human behavior.
Though it implies such a causal relation, the para intends mainly to link the impact on species to human behavior.

B. It explains how environmental damage can cause effects that last for generations.
The first para doesn't suggest that the effect can "last for generations" as only the impact on first generation is all what's talked about. Nothing is mentioned about what happens to the offspring, if any is birthed.

C. It stresses that oxygen levels are paramount in determining ocean survival rates.
The author doesn't address "Ocean survival rate" in general.

D. It pinpoints the cause of species destruction in specific marine habitats. 
Right. The author attempts to explain and link the destructive effects in dead zones to the human behavior(the primary cause).

E. It argues that survival in the changing ocean depends on genetic factors.
First para never talks about any genetic factor.

800gal · Answer

Answers ---> 1. B 2. C 3. D

REASONING :

Ag. runoff + ind. pollutants —> hypoxic areas (hypoxic? lack of O2 mentioned, must mean lack of O2) 
Hypoxia —> threat to marine species

Some survive, Some succ. escape “dead zones”than others.

Escaped ones go to unfamiliar habitats —> can’t defend, less likely to be fertile.

Infertility —> linked to lack of O2 in original env.

Lack of Fertility —> most havoc on F members of Species.

Main Idea P1 —> Introduces hypoxic zones, effects on species survival (defending + fertility)

Threat known but new threat revealed now that increases prob. of species survival.

Low levels of O2 affect gender control genes —> induce sex changes —> More males less females —> repr. affected.

Quantity + Quality of eggs in F. affected. Surviving F —> Functionally Infertile OR ill equipped offspring produced.

Main Idea P2 —-> Expands on hypoxic zone threat on species survival.

Main Idea Passage —> Introduce Hyp. zones, effects on species + specific effects on survival

Tone of Author —> Analytical.

1. The author's primary objective in discussing hypoxic zones is to explain how they
 
 Primary Objective /Main Point/ Main Idea questions MUST address the overarching theme of the entire passage. So wrong answers to look out for would be ones that are too specific or not related to the passage at all. 
  A. compromise the health of marine ecosystems.  The passage addresses how certain species can be adversely affected. An ecosystem includes all species of all organisms including plants in the environment mentioned. This is incorrect.
  B. contribute to the extinction of certain marine life. CORRECT ,  The passage proceeds (in both paragraphs) to expand on the effects of hypoxic zones on CERTAIN SPECIES OF FISH (marine life). It even proceeds to discuss how the reproduction, defence against predators and continued survival of these species are affected, which can address their extinction. 
  C. alter the chemical composition of ocean habitats.  This choice is neither the primary objective of the passage nor addressed in the passage. The chemical composition change in the ocean habitats has not been mentioned and hence this choice is OUT OF SCOPE.
  D. have been linked to altered gene expression in fish.   This is a very specific detail mentioned in paragraph 2, however it is mentioned as part of the overarching theme of HOW certain marine life is affected by hypoxic zones - TOO SPECIFIC. 
  E. are depleted of oxygen over long periods of time.   This is a detail mentioned in paragraph one - In fact it is the definition of hypoxia. However this specific detail isn't the theme of the paragraph. Hence this choice is TOO SPECIFIC.

2. The passage implies that fish that can survive in hypoxic zones
 
 Implies --> Given the passage details are true, the correct answer choice MUST BE TRUE.

A. have developed a tolerance for anoxia as the species evolved.  
The harmful effects of hypoxic zones on the reproduction and subsequent survival is mentioned in the passage, however tolerance to hypoxia is not addressed. Moreover, it can be reasonably inferred that a good majority of the species of fish cannot survive with hypoxia I.E no/ little tolerence to hypoxia. ( BTW anoxia == hypoxia so this isn't why the choice is wrong in case this has occurred to anyone.)
  B. belong to species that are indigenous to less oxygenated areas of the ocean.  
This cannot be supported by any detail in the passage, all the passage says is that some fish may survive these zones. 
  C. suffer damage that is more apparent in their offspring than in themselves. CORRECT  
Paragraph 2 correctly provides support to this inference. It mentions that the fish that survive can be "functionally" infertile or produce "biologically inequipped" offspring. It can be reasonably inferred that the surviving fish may or may not have as many apparent harmful effects, however the offspring of these fish can be affected. 
  D. must move to healthier waters in order to reproduce.  
In paragraph two, the implications of fish reproducing in hypoxic waters is mentioned. Therefore the fish that can survive these zones CAN reproduce in these zones, regardless of the consequences.
  E. rely on a biological self-defense mechanism to compensate for the oxygen depletion.  
This choice is out of scope, there is not a single detail in the passage that can support this inference. There are no mentions of a self defense mechanism. Escaping the zones is mentioned, but this is certainly not a biological self defense mechanism.

3. The first paragraph primarily performs which of the following functions in the passage?
 
 The first paragraph was placed there to fulfill some role. A passage map (attached above) is very useful for these questions.
 
  A. It links compositional changes in ocean water to irresponsible human behavior.  
This is implied in the very first sentence as to what causes hypoxic ocean zones (agricultural runoff +industrial wastewater pollutants) . The paragraph's role is not to discuss only this specific detail.
  B. It explains how environmental damage can cause effects that last for generations.  
The first paragraph only introduces this idea in it's last sentence. This is in fact hinted at and explored in the second paragraph which discusses survival and reproduction of the species.
  C. It stresses that oxygen levels are paramount in determining ocean survival rates. 
 This is a specific detail mentioned in the first paragraph, not what the passage stands for as a whole.
  D. It pinpoints the cause of species destruction in specific marine habitats.
CORRECT.   If you read paragraph 1 again, it introduces and defines hypoxic zones, explains how it is a threat to certain species and mentions how it can badly affect the reproduction and survival of the species. 
  E. It argues that survival in the changing ocean depends on genetic factors.  
This is neither addressed in paragraph 1 or 2. The passage addresses the effect of the changing ocean ON the genes of certain fish. OUT OF SCOPE.

Anki2609 · Answer

Passage Map:
1. Talks about how Hypoxic condition affect marine life. Issue even when the fish migrate from this place.
2. The Hypoxic environment effect on fish and how it may lead to extinction

The passage doesn't contain any argument. it is list of facts and statement

1. The author's primary objective in discussing hypoxic zones is to explain how they

A. compromise the health of marine ecosystems. -  Yes. this is what author talks about how the marine life is facing issue because of hypoxic zones  
B. contribute to the extinction of certain marine life.  Not exactly. It talks about fish as whole but not pinpoint a particular species 
C. alter the chemical composition of ocean habitats.   It decreases the oxygen in water but that is not the main point of the passage 
D. have been linked to altered gene expression in fish.  This is talked about in later part but we can have a broader scope  
E. are depleted of oxygen over long periods of time.   Not the primary purpose. this is said in 1 sentence only

2. The passage implies that fish that can survive in hypoxic zones
 
A. have developed a tolerance for anoxia as the species evolved. 
B. belong to species that are indigenous to less oxygenated areas of the ocean.
 From statement - "hypoxic, a condition that poses serious threats to marine species that require abundant oxygen to survive. Some fish may be able to tolerate this environment". - As the oxygen decreases and the fish that survives must be of species that uses less oxygen  
C. suffer damage that is more apparent in their offspring than in themselves.  Damage is apparent on the current species too e.g. infertility 
D. must move to healthier waters in order to reproduce.  Moving to healtier water also leads to infertility 
E. rely on a biological self-defense mechanism to compensate for the oxygen depletion.  We can't be sure of this as how they compensate oxygen depletion

3. The first paragraph primarily performs which of the following functions in the passage?

A. It links compositional changes in ocean water to irresponsible human behavior.  Not the primary focus of passage 
B. It explains how environmental damage can cause effects that last for generations.  First paragraph only talks about infertility 
C. It stresses that oxygen levels are paramount in determining ocean survival rates.  Oxygen levels are important but that is not the primary purpose 
D. It pinpoints the cause of species destruction in specific marine habitats.  Yes. it talks about how hypoxic condition affects marine life in particular habitat 
E. It argues that survival in the changing ocean depends on genetic factors.  No. This is not discussed in passage

Rohitq · Answer

Passage Brief

Introduction of Hypoxic condition ----> this is causing devastating effect on the marine life---> then he explains how it causes havoc in marine species that require more oxygen to survive

Para 2 ---> It is extension of the effects stated above ---> additional effect is introduced----> lack of oxygen causing change in species sex and the impact on female survivor and its offspring ----> end result is pushing the population to extinction

Lets look at questions

1. The author's primary objective in discussing hypoxic zones is to explain how they

A. compromise the health of marine ecosystems. ( This is close, since the passage talks mostly about the effects of Hypoxic condition, which can accelerate marine species extinction or have a devastating impact on their health )
B.  contribute to the extinction of certain marine life . ( This is one of its contribution but overall the hypoxic condition is taking a toll over the marine health, and there are various effects discussed in para 2 , hence option A is much comprehensive )
C.  alter the chemical composition of ocean habitats.  ( We know it reduces the oxygen in ocean waters, chemical composition is far fetched and can be considered OFS )
D.  have been linked to altered gene expression in fish.  ( From para 2 we know it alters the sex in fish and have an impact on the fertility of females leading to effect on its offspring, hence this is also OFS )
E.  are depleted of oxygen over long periods of time.  ( Its true that they result in oxygen reduction in oceans, which impacts the marine life but if we have to look at the primary function of the passage it is basically discussing the health impact in marine life from a condition called Hypoxy )

2. The passage implies that fish that can survive in hypoxic zones
 
A. have developed a tolerance for anoxia as the species evolved. ( This can be found in para 1   "Some fish may be able to tolerate this environment, and some species are more successful than others at escaping from these "dead zones." ,  hence this is a possible answer) 
B.  belong to species that are indigenous to less oxygenated areas of the ocean.  ( We cannot find a evidence in para to support this idea, hence it is OFS )
C.  suffer damage that is more apparent in their offspring than in themselves.  ( This is partly true, and I feel this option made me take more time to reach to a conclusion after finding out that this statement is not completely true. The evidence is there in para 2 where it is mentioned   "It appears that low levels of dissolved oxygen inhibit the function of genes that control gender specificity in some fish, which means that the hypoxic water can induce sex changes in certain species. This causes an overabundance of males and reduces their opportunities to reproduce. Furthermore, the hypoxic waters compromise the quantity and quality of the female eggs. The females that do survive their deadly habitat may therefore either be functionally infertile or may produce offspring ",  hence we can safely say both suffer damage considering one is a understatement )
D.  must move to healthier waters in order to reproduce.  ( but the question is on the fish that can survive the zone and not move to other place, this is one of the reason for their movement since they cannot survive the hypoxic zone  )
E.  rely on a biological self-defense mechanism to compensate for the oxygen depletion.  ( This is OFS, we cannot find any supporting evidence from the passage on the self defense mechanism)

3. The first paragraph primarily performs which of the following functions in the passage?

A.  It links compositional changes in ocean water to irresponsible human behavior.   (There is a small mention of agricultural run off and industrial pollution, but then the para is not concerned about the human impact. It basically wants to discuss the Hypoxic condition and its impact) 
B.  It explains how environmental damage can cause effects that last for generations . (  in para 2 it is evident that the offspring are impacted and also the fishes, but this is not the case with para 1. Para 1 explains a condition in ocean and then analyze its impact on the marine life for the one that can tolerate and other that migrates to oxygen abundant spot. )
C.  It stresses that oxygen levels are paramount in determining ocean survival rates . ( Para 1 do mentions that lack of oxygen have an impact on fishes but then "ocean survival rates" that is too generic a statement. We are only discussing on some particular part of ocean where this condition occurred .  This option is still close if we do not find any good answers )
D. It pinpoints the cause of species destruction in specific marine habitats. ( I think we found a good choice, yes para 1 introduces a condition which is causing species destruction. So we have the cause and the para is pinpointing at that cause and its impact only(there could be many others)."in specific marine habitats." this statement is making the answer choice more precise, hence we got our correct choice )
E.  It argues that survival in the changing ocean depends on genetic factors . ( Clearly OFS, we cannot find any evidence of genetic factors in the para 1 )

sunitapandey · Answer

First Paragraph:
 Due to certain factors large areas of ocean have become hypoxic. 
 This threatens marine species that require more oxygen.
 Some fish survive others escape this dead zone.
 In new habitat fish cannot defend themselves against predators and become infertile(owning to their original habitat that lacked oxygen).

Second Paragraph:
 Recent study reveals hypoxic zone can lead to species extinction.
 Reduced oxygen --> inhibits function that control gender specificity in some fish -->leading to sex change in some fish--> leada to more male fish
 Hypoxic water compromises the quantity and quality of female eggs.
  Female fish that survive hypoxic water either become infertile or produce biologically ill equipped offsprings which cannot contribute to population growth.

1. The author's primary objective in discussing hypoxic zones is to explain how they

A. compromise the health of marine ecosystems.
Correct- as it includes all the problems discussed namely -species extinction, altered gene expression
B. contribute to the extinction of certain marine life.
This is discussed in the passage but so is option D therefore going with Option A as that is more generic
C. alter the chemical composition of ocean habitats.
Not discussed specifically in the passage
D. have been linked to altered gene expression in fish.
Same as B
E. are depleted of oxygen over long periods of time
Passage doesn't talk about how long oxygen was depleted from hypoxic zone

2. The passage implies that fish that can survive in hypoxic zones

A. have developed a tolerance for anoxia as the species evolved.
Not discussed
B. belong to species that are indigenous to less oxygenated areas of the ocean.
Not discussed
C. suffer damage that is more apparent in their offspring than in themselves.
Correct "produce offspring that are biologically ill equipped"
D. must move to healthier waters in order to reproduce.
Not discussed
E. rely on a biological self-defense mechanism to compensate for the oxygen depletion.
Not Discussed

3. The first paragraph primarily performs which of the following functions in the passage?

A. It links compositional changes in ocean water to irresponsible human behavior.
Not discussed
B. It explains how environmental damage can cause effects that last for generations.
Not discussed
C. It stresses that oxygen levels are paramount in determining ocean survival rates.
Correct
D. It pinpoints the cause of species destruction in specific marine habitats.
Passage talks about the effect of lack of oxygen on species that require abundant oxygen
E. It argues that survival in the changing ocean depends on genetic factors.
Not discussed

irisjojojo · Answer

This question set takes more time than I've expected. I feel like the questions, not the article, is the toughest. Question 1: A The question is looking for the main goal of discussing "hypoxic zones" A --> looks good B --> "extinction" is not explicitly mentioned in the passage. It seems to me going to far C --> "alter the chemical composition" --> not the focus (the focus should be the "influence" of the change) D --> "gene expression" --> not mentioned E --> definitely not the focus Question 2: B Ask for the "lucky fish" A --> not sure if "anoxia" is mentioned in the passage (not within my knowledge) C --> "The females that do survive their deadly habitat may therefore either be functionally infertile or may produce offspring that are biologically ill equipped to contribute to population growth and help ensure survival of the species." Can't deduct which one suffers more damage D --> nope, the article instead states "but they escape to unfamiliar habitats where they are less capable of defending themselves against predators and are less likely to be fertile." E --> self-defense mechanism? seems like a new idea... B can be traced back to "the infertility is linked directly to the lack of oxygen in the environment from which they escaped" = belong to species that are indigenous to less oxygenated areas of the ocean --> therefore, it's the answer Question 3: D A --> definitely no (the concept of "irresponsible human behavior" is not mentioned) B --> It seems to me more like what the second paragraph is talking about C --> "ocean survival rates" is somewhat different from "infertility rate" . thus, I would not prefer this answer E --> "genetic factors" are not mentioned in the first paragraph D --> the cause = hypoxic; specific marine habitats = "marine species that require abundant oxygen to survive" seems good!

akash2703 · Answer

Notes:-
Para1- Pollutants making hypoxic environment (with lack of oxygen) and this causes the marine species survival.
- some can adapt the environment
- some move to next habitat for survival (but can't survive)
- female infertility

Para2- Same tone is continued mentioning additional threats
- sex changes (abundance of male species)
- compromises the female eggs, who remain in the same env. and those moved out lose fertility.

Question1 - OA- B

1. The author's primary objective in discussing hypoxic zones is to explain how they

A. compromise the health of marine ecosystems.
 
B. contribute to the extinction of certain marine life.
   
C. alter the chemical composition of ocean habitats.
 
D. have been linked to altered gene expression in fish.
 
E. are depleted of oxygen over long periods of time.

Question: OA- C

2. The passage implies that fish that can survive in hypoxic zones

A. have developed a tolerance for anoxia as the species evolved.
 
B. belong to species that are indigenous to less oxygenated areas of the ocean.
 
C. suffer damage that is more apparent in their offspring than in themselves.
 the females that do survive their deadly habitat may therefore either be functionally infertile or may produce offspring that are biologically ill equipped to contribute to population growth and help ensure survival of the species 
D. must move to healthier waters in order to reproduce.
 
E. rely on a biological self-defense mechanism to compensate for the oxygen depletion.

Question3 OA- C

3. The first paragraph primarily performs which of the following functions in the passage?

A. It links compositional changes in ocean water to irresponsible human behavior.
 
B. It explains how environmental damage can cause effects that last for generations.
 
C. It stresses that oxygen levels are paramount in determining ocean survival rates.
   
D. It pinpoints the cause of species destruction in specific marine habitats.
 
E. It argues that survival in the changing ocean depends on genetic factors.

zyt · Answer

1.  The author's primary objective in discussing hypoxic zones is to explain how they

A. compromise the health of marine ecosystems.  
in first para it is mentioned some fishes are affected some are not , marine ecosystem as such not described.

B. contribute to the extinction of certain marine life .
yes this is clearly mentioned that certain species are more vulnerable

C.  alter the chemical composition of ocean habitat s. 
the altered reproductive capability of fishes more than chemical composition is the objective

]D. have been linked to altered gene expression in fish . 
its is an additional explanation in second paragraph, not the primary of the entire passage.

E. are depleted of oxygen over long periods of time  
periods of time is not mentioned

2. The passage implies that fish that can survive in hypoxic zones

A.   have developed a tolerance for anoxia as the species evolved.    
the fish actually gradually perish due to anoxia, not evolve.

B.   belong to species that are indigenous to less oxygenated areas of the ocean . 
nowhere has indigenous species is mentioned, only that some fish species are able to survive if exposed to hypoxia

C. suffer damage that is more apparent in their offspring than in themselves. 
This is correct as in second paragraph its written that due to inferior egg quality due to hypoxia the offspring produced is not genetically at par with the parent fish and more likely to die.

D .  must move to healthier waters in order to reproduce.  
not as such mentioned anywhere in passage about moving to reproduce.

E.   rely on a biological self-defense mechanism to compensate for the oxygen depletion . 
no self defense is mentioned only thing mentioned in the para graph is affect on genes causing damage to future off spring

3. The first paragraph primarily performs which of the following functions in the passage?

]A. It links compositional changes in ocean water to irresponsible human behavior . 
Humans causing industrial and agricultural waste to pollute is only in the beginning but not the main function of the first paragraph.

B. It explains how environmental damage can cause effects that last for generations.  
Future generations may not be possible if the fishes are extinct so is an irrelevant answer

C. It stresses that oxygen levels are paramount in determining ocean survival rates. 
Yes hypoxia and oxygen levels are important and discussed in first paragraph.

D. It pinpoints the cause of species destruction in specific marine habitats.  
not correct as only hypoxia in the hypoxic marine habitat is discussed, doses not specify the types of marine habitats

E. It argues that survival in the changing ocean depends on genetic factors.  
Previous genetic factors affecting survival not mentioned

Haridas800 · Answer

1 Ans :B. contribute to the extinction of certain marine life.

2 Ans :E. rely on a biological self-defense mechanism to compensate for the oxygen depletion.

3 Ans :C. It stresses that oxygen levels are paramount in determining ocean survival rates.

ktzsikka · Answer

1. The author's primary objective in discussing hypoxic zones is to explain how they

A. compromise the health of marine ecosystems. 
Author mentions this in line1/para2  (threat of hypoxic zones to the marine ecosystem)  and subtly hints the same in line 4 (serious threats to marine species)

B. contribute to the extinction of certain marine life.
correct but have limited scope; choice A is more holistic IMO.

C. alter the chemical composition of ocean habitats.
no such explanation given, hence incorrect

D. have been linked to altered gene expression in fish.
correct but have limited scope

E. are depleted of oxygen over long periods of time.
no such explanation given, hence incorrect

2. The passage implies that fish that can survive in hypoxic zones

A. have developed a tolerance for anoxia as the species evolved.
no such explanation given, hence incorrect

B. belong to species that are indigenous to less oxygenated areas of the ocean.
no such mention, out of scope

C. suffer damage that is more apparent in their offspring than in themselves.  
mentioned in last line of para 2  (The females that do survive their deadly habitat may therefore e ither be functionally infertile or may produce offspring that are biologically ill equipped  to contribute to population growth and help ensure survival of the species.)  Both infertility and ill-equipped offspring indicates that damage is more apparent on offspring.

D. must move to healthier waters in order to reproduce.
no such mention, out of scope

E. rely on a biological self-defence mechanism to compensate for the oxygen depletion
maybe correct but with limited scope

3. The first paragraph primarily performs which of the following functions in the passage?

A. It links compositional changes in ocean water to irresponsible human behaviour.
irresponsible is a quite extreme word for agricultural runoff, hence incorrect

B. It explains how environmental damage can cause effects that last for generations.
this can inferred from para 2 but not from para 1, hence incorrect

C. It stresses that oxygen levels are paramount in determining ocean survival rates.
no such mention, out of scope

D. It pinpoints the cause of species destruction in specific marine habitats.  
Para 1 clearly indicates this  (Due in large ... poses serious threats to marine species that require abundant oxygen to survive)
 
E. It argues that survival in the changing ocean depends on genetic factors.
genetics are mentioned only for  gender specificity

Sajjad1994 · Answer

Hello everyone

This is an interesting passage, although it is short but is hard. Official answers are posted now and below are my comments.

Question #1
Difficulty Level: 700

All those selected answer options C, D, or E might need to rethink their RC strategy. None of these three options was a bit near to the Official answer. The debate can happen only between A and B. A is too broad to be fit into the boundaries of the passage and hence is out while B fits good. The race between A and B made this question hard.

Question #2
Difficulty Level: 550

All those selected answer options A, D, or E might need to rethink their RC strategy. None of these three options was a bit near to the Official answer. There is not much room for debate between options B and C.

Question #3
Difficulty Level: 700

This is the toughest question among these three questions. D is the answer.

Getting questions 1 and 3 wrong is not as bad as getting question 2 wrong is as question #2 is straight forward.

Gaudapada  and  800gal  excellent (10/10)
 ShellyB  (9.5/10)
 ash124  (9/10)

Good explanation (to questions you got correct) from you too  akash2703   zyt

Thank you

Due in large part to agricultural runoff and pollutants from industria

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GMAT Reading Comprehension (RC) Questions

Due in large part to agricultural runoff and pollutants from industria

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