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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
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mbaiseasy wrote:
1. The passage suggests that a lack of modern sanitation would make which of the following most likely to occur?

"Thus, the HYGIENE that helped PREVENT TYPHOID epidemics
indirectly fostered a paralytic polio epidemic
" - Remove HYGIENE then we get the reverse of PREVENTING TYPHOID


ANSWER: (C) An epidemic of typhoid

2. According to the passage, the outbreak of dengue hemorrhagic fever in the 1950's occurred for which of the following reasons?

"an outbreak of dengue hemor-
rhagic fever became an epidemic in Asia in the 1950's
because of ecological changes that caused Aedes aegypti,
(25) the mosquito that transmits the dengue virus, to proliferate
" - PROLIFERATE / INCREASE in NUMBER


ANSWER: (B) The mosquito Aedes aegypti became more numerous.


3. It can be inferred from the passage that Lyme disease has become prevalent in parts of the United States because of which of the following?

"increased outdoor recreational activities in the
deer's habitat" - MORE EXPOSURE TO DEER


ANSWER: (E) An increase in the number of humans who encounter deer ticks


4. Which of the following can most reasonably be concluded about the mosquito Aedes albopictus on the basis of information given in the passage?

"The stage is now set in the United States for a
dengue epidemic because of the inadvertent introduction
and wide dissemination of another mosquito, Aedes
albopictus
" - newly introduced... hence, not native to the US...


A It is native to the United States. They are newly introduced. Hence, out!
B It can proliferate only in Asia. They can cause epidemics in US. Hence, out!
ANSWER: (C) It transmits the dengue virus.
D It caused an epidemic of dengue hemorrhagic fever in the 1950's. This is another breed of mosquito
E It replaced Aedes aegypti in Asia when ecological changes altered Aedes aegypti's habitat. not mentioned

5. Which of the following best describes the organization of the passage?

A A paradox is stated, discussed and left unresolved. Contrasting views mentioned initially but the discussion did not revolve around that...
B Two opposing explanations are presented, argued, and reconciled.Two views introduced but the discussion did not revolve around that

C A theory is proposed and is then followed by descriptions of three experiments that support the theory. no such experiments mentioned

ANSWER: (D) A generalization is stated and is then followed by three instances that support the generalization.

E An argument is described and is then followed by three counterexamples that refute the argument. the examples are not use as counterexamples but just examples of epidemics without genetic evolution

6. Which of the following, if true, would most strengthen the author's assertion about the cause of the Lyme disease outbreak in the United States?

ANSWER: (A) The deer population was smaller in the late nineteenth century than in the mid-twentieth century.
If the deer population was just same as population to day, then the increase in population will be an invalid explanation for the Lyme disease. This eliminate that possibility.




i'm confused about question number 6 - the passage already states that the deer population was smaller in the past. choice a is merely re-stating this fact. strengthening should bring something out of scope into the picture. would love if anyone can explain here. thanks!
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
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mokura wrote:
mbaiseasy wrote:
1. The passage suggests that a lack of modern sanitation would make which of the following most likely to occur?

"Thus, the HYGIENE that helped PREVENT TYPHOID epidemics
indirectly fostered a paralytic polio epidemic
" - Remove HYGIENE then we get the reverse of PREVENTING TYPHOID


ANSWER: (C) An epidemic of typhoid

2. According to the passage, the outbreak of dengue hemorrhagic fever in the 1950's occurred for which of the following reasons?

"an outbreak of dengue hemor-
rhagic fever became an epidemic in Asia in the 1950's
because of ecological changes that caused Aedes aegypti,
(25) the mosquito that transmits the dengue virus, to proliferate
" - PROLIFERATE / INCREASE in NUMBER


ANSWER: (B) The mosquito Aedes aegypti became more numerous.


3. It can be inferred from the passage that Lyme disease has become prevalent in parts of the United States because of which of the following?

"increased outdoor recreational activities in the
deer's habitat" - MORE EXPOSURE TO DEER


ANSWER: (E) An increase in the number of humans who encounter deer ticks


4. Which of the following can most reasonably be concluded about the mosquito Aedes albopictus on the basis of information given in the passage?

"The stage is now set in the United States for a
dengue epidemic because of the inadvertent introduction
and wide dissemination of another mosquito, Aedes
albopictus
" - newly introduced... hence, not native to the US...


A It is native to the United States. They are newly introduced. Hence, out!
B It can proliferate only in Asia. They can cause epidemics in US. Hence, out!
ANSWER: (C) It transmits the dengue virus.
D It caused an epidemic of dengue hemorrhagic fever in the 1950's. This is another breed of mosquito
E It replaced Aedes aegypti in Asia when ecological changes altered Aedes aegypti's habitat. not mentioned

5. Which of the following best describes the organization of the passage?

A A paradox is stated, discussed and left unresolved. Contrasting views mentioned initially but the discussion did not revolve around that...
B Two opposing explanations are presented, argued, and reconciled.Two views introduced but the discussion did not revolve around that

C A theory is proposed and is then followed by descriptions of three experiments that support the theory. no such experiments mentioned

ANSWER: (D) A generalization is stated and is then followed by three instances that support the generalization.

E An argument is described and is then followed by three counterexamples that refute the argument. the examples are not use as counterexamples but just examples of epidemics without genetic evolution

6. Which of the following, if true, would most strengthen the author's assertion about the cause of the Lyme disease outbreak in the United States?

ANSWER: (A) The deer population was smaller in the late nineteenth century than in the mid-twentieth century.
If the deer population was just same as population to day, then the increase in population will be an invalid explanation for the Lyme disease. This eliminate that possibility.

i'm confused about question number 6 - the passage already states that the deer population was smaller in the past. choice a is merely re-stating this fact. strengthening should bring something out of scope into the picture. would love if anyone can explain here. thanks!


OE #1: Lines 14–15 show that typhoid epidemics were prevented by modern sanitation; therefore, typhoid might breakout in the absence of modern sanitation.

OE #2 : The lines 24–28 mention outbreak became an epidemic in Asia because of ecological changes that caused Aedes aegypti, the mosquito that transmits the dengue virus, to proliferate

OE #3: To make an inference about Lyme disease, examine the discussion of Lyme disease in lines 16–24. As the deer population grows and as humans encroach on the deer habitat, more people encounter deer ticks and become infected with the disease.

OE #4 : An inference is drawn from stated information rather than explicitly stated. Aedes albopictus is mentioned in the final sentence of the passage, which says that this mosquito was inadvertently introduced into the United States and has spread widely. Author states that the stage is now set in the United States for a dengue epidemic. It is reasonable to infer that this mosquito can transmit the dengue virus.

OE #5 : Analyze the structure of the passage in order to answer a question about how the passage is organized. Three specific examples—Polio, Lyme disease, and Dengue hemorrhagic fever—are used to support a general statement

OE#6 : The author blames the recent prevalence of Lyme disease on the rise in the deer population and the growth of the suburbs, with people spending more time outside in the deer’s habitat.
For question number 6--If you read the lines 15-12 and the OE " The author blames the recent prevalence of Lyme disease on the rise in the deer population and the growth of the suburbs, with people spending more time outside in the deer’s habitat." you will find that option A -[The deer population was smaller in the late nineteenth century than in the mid-twentieth century] will strengthen the authors assertion
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
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dentobizz wrote:
OE #1: Lines 14–15 show that typh....

OE #5 : Analyze the structure of the passage in order to answer a question about how the passage is organized. Three specific examples—Polio, Lyme disease, and Dengue hemorrhagic fever—are used to support a general statement

....will strengthen the authors assertion


I can understand that option D is correct because it states "three instances" and that option C incorrectly states "three experiments" but I'm finding it difficult to understand what is meant by generalization.
According to my understanding, generalization may or may not be true and is drawn by various statements. Whereas, the passage states that scientists have discovered the importance of..
I concluded that since scientist has discovered the reason, the word theory suits better than generalization (both are not the correct words imo)

Although, I see that experiments and instances completely clears the ambiguity of the right answer, is the usage of word generalization preferred more than theory?
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
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Need some help with Q 1....
I can understand why C is correct, but D is also correct.
The hygiene postponed the appearance of polio from babies to adults...
So if there was no hygiene, it would attack babies again....
Anyone?
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
rohitmanglik wrote:
ronr34 wrote:
Need some help with Q 1....
I can understand why C is correct, but D is also correct.
The hygiene postponed the appearance of polio from babies to adults...
So if there was no hygiene, it would attack babies again....
Anyone?



+1 same doubt

anyone? D looks equally correct.


Even I have the same doubt !! Could anyone clarify on this?
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
2
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dentobizz wrote:
mokura wrote:
mbaiseasy wrote:
1. The passage suggests that a lack of modern sanitation would make which of the following most likely to occur?

"Thus, the HYGIENE that helped PREVENT TYPHOID epidemics
indirectly fostered a paralytic polio epidemic
" - Remove HYGIENE then we get the reverse of PREVENTING TYPHOID


ANSWER: (C) An epidemic of typhoid

2. According to the passage, the outbreak of dengue hemorrhagic fever in the 1950's occurred for which of the following reasons?

"an outbreak of dengue hemor-
rhagic fever became an epidemic in Asia in the 1950's
because of ecological changes that caused Aedes aegypti,
(25) the mosquito that transmits the dengue virus, to proliferate
" - PROLIFERATE / INCREASE in NUMBER


ANSWER: (B) The mosquito Aedes aegypti became more numerous.


3. It can be inferred from the passage that Lyme disease has become prevalent in parts of the United States because of which of the following?

"increased outdoor recreational activities in the
deer's habitat" - MORE EXPOSURE TO DEER


ANSWER: (E) An increase in the number of humans who encounter deer ticks


4. Which of the following can most reasonably be concluded about the mosquito Aedes albopictus on the basis of information given in the passage?

"The stage is now set in the United States for a
dengue epidemic because of the inadvertent introduction
and wide dissemination of another mosquito, Aedes
albopictus
" - newly introduced... hence, not native to the US...


A It is native to the United States. They are newly introduced. Hence, out!
B It can proliferate only in Asia. They can cause epidemics in US. Hence, out!
ANSWER: (C) It transmits the dengue virus.
D It caused an epidemic of dengue hemorrhagic fever in the 1950's. This is another breed of mosquito
E It replaced Aedes aegypti in Asia when ecological changes altered Aedes aegypti's habitat. not mentioned

5. Which of the following best describes the organization of the passage?

A A paradox is stated, discussed and left unresolved. Contrasting views mentioned initially but the discussion did not revolve around that...
B Two opposing explanations are presented, argued, and reconciled.Two views introduced but the discussion did not revolve around that

C A theory is proposed and is then followed by descriptions of three experiments that support the theory. no such experiments mentioned

ANSWER: (D) A generalization is stated and is then followed by three instances that support the generalization.

E An argument is described and is then followed by three counterexamples that refute the argument. the examples are not use as counterexamples but just examples of epidemics without genetic evolution

6. Which of the following, if true, would most strengthen the author's assertion about the cause of the Lyme disease outbreak in the United States?

ANSWER: (A) The deer population was smaller in the late nineteenth century than in the mid-twentieth century.
If the deer population was just same as population to day, then the increase in population will be an invalid explanation for the Lyme disease. This eliminate that possibility.

i'm confused about question number 6 - the passage already states that the deer population was smaller in the past. choice a is merely re-stating this fact. strengthening should bring something out of scope into the picture. would love if anyone can explain here. thanks!


OE #1: Lines 14–15 show that typhoid epidemics were prevented by modern sanitation; therefore, typhoid might breakout in the absence of modern sanitation.

OE #2 : The lines 24–28 mention outbreak became an epidemic in Asia because of ecological changes that caused Aedes aegypti, the mosquito that transmits the dengue virus, to proliferate

OE #3: To make an inference about Lyme disease, examine the discussion of Lyme disease in lines 16–24. As the deer population grows and as humans encroach on the deer habitat, more people encounter deer ticks and become infected with the disease.

OE #4 : An inference is drawn from stated information rather than explicitly stated. Aedes albopictus is mentioned in the final sentence of the passage, which says that this mosquito was inadvertently introduced into the United States and has spread widely. Author states that the stage is now set in the United States for a dengue epidemic. It is reasonable to infer that this mosquito can transmit the dengue virus.

OE #5 : Analyze the structure of the passage in order to answer a question about how the passage is organized. Three specific examples—Polio, Lyme disease, and Dengue hemorrhagic fever—are used to support a general statement

OE#6 : The author blames the recent prevalence of Lyme disease on the rise in the deer population and the growth of the suburbs, with people spending more time outside in the deer’s habitat.
For question number 6--If you read the lines 15-12 and the OE " The author blames the recent prevalence of Lyme disease on the rise in the deer population and the growth of the suburbs, with people spending more time outside in the deer’s habitat." you will find that option A -[The deer population was smaller in the late nineteenth century than in the mid-twentieth century] will strengthen the authors assertion


If option A strengthens the author's assertion then so does the option B. Because author also stated that because of more people spending time outside in the deer's habitat Lyme disease rose at that time. That means peoples' interest in outdoor recreational activities also led to spreading of the Lyme disease.
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
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rohitmanglik wrote:
ronr34 wrote:
Need some help with Q 1....
I can understand why C is correct, but D is also correct.
The hygiene postponed the appearance of polio from babies to adults...
So if there was no hygiene, it would attack babies again....
Anyone?



+1 same doubt

anyone? D looks equally correct.


Hello,

In question 1, D is not correct because says 'An epidemic of paralytic polio among infants'. According to lines 10-12, we know that infant polio does not incurs in paralysis.

Best,
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
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arpit2093 wrote:
For Question no. 6, How is B wrong ?


Hello,

According to lines 16 to 22, "Interest in outdoor recreation began to grow in the recently late nineteenth century". That's why letter B is wrong.

Note that the transmission of Lyme disease "occurred sporadically [in nineteenth century]", but became prevalent recently when "Interest in outdoor recreation began to grow".

Best,
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
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p1 - reasons for epidemic - no genetic mutations - example
P2 - 2 more example on the same line as above.
Main point - with example it is explained that epidemic can spread.
tone - moderate/normal.

1. The passage suggests that a lack of modern sanitation would make which of the following most likely to occur?
define in P1. - Thus, the hygiene that helped prevent typhoid epidemics indirectly fostered a paralytic polio epidemic.
C An epidemic of typhoid
--------------------------------------------------
2. According to the passage, the outbreak of dengue hemorrhagic fever in the 1950's occurred for which of the following reasons?

Similarly, an outbreak of dengue hemorrhagic fever became an epidemic in Asia in the 1950's because of ecological changes that caused Aedes aegypti, the mosquito that transmits the dengue virus, to proliferate. The stage is now set in the United States for a dengue epidemic because of the inadvertent introduction and wide dissemination of another mosquito, Aedes albopictus.

A The mosquito Aedes aegypti was newly introduced into Asia. - no
B The mosquito Aedes aegypti became more numerous. - Yes
C The mosquito Aedes albopictus became infected with the dengue virus. - yes
D Individuals who would normally acquire immunity to the dengue virus as infants were not infected until later in life. - no
E More people began to visit and inhabit areas in which mosquitos live and breed. - NO

between B and C --- Well if B was not there then C could not be a case. and it would never been a case of epidemic. B is best of the lot.

--------------------------------------------------
3. It can be inferred from the passage that Lyme disease has become prevalent in parts of the United States because of which of the following?
given in P2.
largely due to an increase in the deer population that occurred simultaneously with the growth of the suburbs and increased outdoor recreational activities in the deer's habitat.

E An increase in the number of humans who encounter deer ticks - yes

--------------------------------------------------

4. Which of the following can most reasonably be concluded about the mosquito Aedes albopictus on the basis of information given in the passage?
Last sentence.
The stage is now set in the United States for a dengue epidemic because of the inadvertent introduction and wide dissemination of another mosquito, Aedes albopictus.
A It is native to the United States. - no
B It can proliferate only in Asia. - no
C It transmits the dengue virus. - yes
D It caused an epidemic of dengue hemorrhagic fever in the 1950's. - too broad.
E It replaced Aedes aegypti in Asia when ecological changes altered Aedes aegypti's habitat. - no

---------------------------------------------------

5. Which of the following best describes the organization of the passage?

A A paradox is stated, discussed and left unresolved. - no
B Two opposing explanations are presented, argued, and reconciled. - no
C A theory is proposed and is then followed by descriptions of three experiments that support the theory. - those were not experiments.
D A generalization is stated and is then followed by three instances that support the generalization. - best of lot.
E An argument is described and is then followed by three counterexamples that refute the argument. - no

--------------------------------------------------
6. Which of the following, if true, would most strengthen the author's assertion about the cause of the Lyme disease outbreak in the United States?
Lyme disease is caused by bacteria that are transmitted by deer ticks. It occurred only sporadically during the late nineteenth century largely due to an increase in the deer population that occurred simultaneously with the growth of the suburbs and increased outdoor recreational activities in the deer's habitat.

A The deer population was smaller in the late nineteenth century than in the mid-twentieth century. - yes
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
"by then, modern sanitation was able to delay exposure to polio until adolescence or adulthood, at which time polio infection produced paralysis. Previously, infection had occurred during infancy, when it typically provided lifelong immunity without paralysis. Thus, the hygiene that helped prevent typhoid epidemics indirectly fostered a paralytic polio epidemic. "

Not able to understand clearly. Can someone explain the meaning
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
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mallya12 wrote:
"by then, modern sanitation was able to delay exposure to polio until adolescence or adulthood, at which time polio infection produced paralysis. Previously, infection had occurred during infancy, when it typically provided lifelong immunity without paralysis. Thus, the hygiene that helped prevent typhoid epidemics indirectly fostered a paralytic polio epidemic. "

Not able to understand clearly. Can someone explain the meaning


Alright, let me help you with this:

Poliomyelitis, for example, emerged as an epidemic in the United States in the twentieth century ( Poliomyelitis was already present in the U.S, but in the

20th century it emerged as an epidemic. Before that its presence may have been less severe)
; by then (In the 20th century), modern

sanitation was able to delay exposure to polio until adolescence or adulthood (modern sanitation was good and because of which polio exposure was delayed

till adulthood)
, at which time polio infection produced paralysis (This means , if polio virus infects you in adulthood, then this can lead to paralysis)

. Previously (Before this, when good sanitation facility was not there), infection had occurred during infancy(this polio

infection used to occur in the childhood)
, when it (the occurence of polio in childhood) typically provided lifelong immunity without

paralysis (means occurence of polio in childhood provided lifelong immunity against paralysis). Thus, the hygiene that helped prevent typhoid

epidemics indirectly fostered a paralytic polio epidemic. (Thus, modern hygiene that helped preventing typhoid, indirectly supported paralytic polio epidemic.

Because of more hygiene polio occurs only after adulthood and in adulthood polio infection produced paralysis. But this does not happen when polio occurs in childhood

because of non hygiene conditions)


Conclusion :

More hygiene , no typhoid , but polio infects in adulthood, and polio in adulthood leads to paralysis.

Less hygiene, typhoid, but polio infects in childhood, but no paralysis.


Hope this helps.
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
AkshdeepS wrote:
mallya12 wrote:
"by then, modern sanitation was able to delay exposure to polio until adolescence or adulthood, at which time polio infection produced paralysis. Previously, infection had occurred during infancy, when it typically provided lifelong immunity without paralysis. Thus, the hygiene that helped prevent typhoid epidemics indirectly fostered a paralytic polio epidemic. "

Not able to understand clearly. Can someone explain the meaning


Alright, let me help you with this:

Poliomyelitis, for example, emerged as an epidemic in the United States in the twentieth century ( Poliomyelitis was already present in the U.S, but in the

20th century it emerged as an epidemic. Before that its presence may have been less severe)
; by then (In the 20th century), modern

sanitation was able to delay exposure to polio until adolescence or adulthood (modern sanitation was good and because of which polio exposure was delayed

till adulthood)
, at which time polio infection produced paralysis (This means , if polio virus infects you in adulthood, then this can lead to paralysis)

. Previously (Before this, when good sanitation facility was not there), infection had occurred during infancy(this polio

infection used to occur in the childhood)
, when it (the occurence of polio in childhood) typically provided lifelong immunity without

paralysis (means occurence of polio in childhood provided lifelong immunity against paralysis). Thus, the hygiene that helped prevent typhoid

epidemics indirectly fostered a paralytic polio epidemic. (Thus, modern hygiene that helped preventing typhoid, indirectly supported paralytic polio epidemic.

Because of more hygiene polio occurs only after adulthood and in adulthood polio infection produced paralysis. But this does not happen when polio occurs in childhood

because of non hygiene conditions)


Conclusion :

More hygiene , no typhoid , but polio infects in adulthood, and polio in adulthood leads to paralysis.

Less hygiene, typhoid, but polio infects in childhood, but no paralysis.


Hope this helps.


Thanks a lot. Nicely Explained.
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
mokura wrote:
mbaiseasy wrote:
1. The passage suggests that a lack of modern sanitation would make which of the following most likely to occur?

"Thus, the HYGIENE that helped PREVENT TYPHOID epidemics
indirectly fostered a paralytic polio epidemic
" - Remove HYGIENE then we get the reverse of PREVENTING TYPHOID


ANSWER: (C) An epidemic of typhoid

2. According to the passage, the outbreak of dengue hemorrhagic fever in the 1950's occurred for which of the following reasons?

"an outbreak of dengue hemor-
rhagic fever became an epidemic in Asia in the 1950's
because of ecological changes that caused Aedes aegypti,
(25) the mosquito that transmits the dengue virus, to proliferate
" - PROLIFERATE / INCREASE in NUMBER


ANSWER: (B) The mosquito Aedes aegypti became more numerous.


3. It can be inferred from the passage that Lyme disease has become prevalent in parts of the United States because of which of the following?

"increased outdoor recreational activities in the
deer's habitat" - MORE EXPOSURE TO DEER


ANSWER: (E) An increase in the number of humans who encounter deer ticks


4. Which of the following can most reasonably be concluded about the mosquito Aedes albopictus on the basis of information given in the passage?

"The stage is now set in the United States for a
dengue epidemic because of the inadvertent introduction
and wide dissemination of another mosquito, Aedes
albopictus
" - newly introduced... hence, not native to the US...


A It is native to the United States. They are newly introduced. Hence, out!
B It can proliferate only in Asia. They can cause epidemics in US. Hence, out!
ANSWER: (C) It transmits the dengue virus.
D It caused an epidemic of dengue hemorrhagic fever in the 1950's. This is another breed of mosquito
E It replaced Aedes aegypti in Asia when ecological changes altered Aedes aegypti's habitat. not mentioned

5. Which of the following best describes the organization of the passage?

A A paradox is stated, discussed and left unresolved. Contrasting views mentioned initially but the discussion did not revolve around that...
B Two opposing explanations are presented, argued, and reconciled.Two views introduced but the discussion did not revolve around that

C A theory is proposed and is then followed by descriptions of three experiments that support the theory. no such experiments mentioned

ANSWER: (D) A generalization is stated and is then followed by three instances that support the generalization.

E An argument is described and is then followed by three counterexamples that refute the argument. the examples are not use as counterexamples but just examples of epidemics without genetic evolution

6. Which of the following, if true, would most strengthen the author's assertion about the cause of the Lyme disease outbreak in the United States?

ANSWER: (A) The deer population was smaller in the late nineteenth century than in the mid-twentieth century.
If the deer population was just same as population to day, then the increase in population will be an invalid explanation for the Lyme disease. This eliminate that possibility.




i'm confused about question number 6 - the passage already states that the deer population was smaller in the past. choice a is merely re-stating this fact. strengthening should bring something out of scope into the picture. would love if anyone can explain here. thanks!


Hi

I have the same question. It seems that A is merely a paraphrase, and I would expect something slightly out of scope to lend more support for the argument.

Thanks

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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
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Passage Map: Discuss non-mutated viral epidemics
P1: Describe how non-mutated viral epidemics occur and examples
P2: Provide examples of non-mutated viral epidemics and reasons for their prevalence

Question 1

We are told that modern sanitisation or "hygiene" "helped prevent typhoid. So logically a lack of modern sanitation could lead to greater incidence of typhoid since we are removing something that prevents it!

Thus C is correct.

Here's why the other answers are wrong
A - lyme disease and hygiene have no connection in this passage -Wrong
B - no, dengue is caused by mosquitos. Hygiene isn't connected to it in the passage.
D - no because we are told that Polio only becomes paralytic in adulthood
E - no for the reasons stated in D.

Question 6
The author asserts that Lyme disease became prevalent in parts of the US because of an increase in the deer population, and growth of the number of suburbs and amount of people engaging in outdoor activities near dear habitats.

A is correct because it underpins a premise made in the assertion - that deer populations grew.
B although I chose B, I see that it is incorrect because of the timing of the activity. We are only told that outdoor recreation increased recently (after deer population grew), so an increase in outdoor recreation in the late 19th century doesn't exactly help us understand why Lyme is prevalent now.
C is incorrect because if anything it weakens. Growth of suburbs helped contribute to the problem, so this statement hampers the assertion made by the author
D is incorrect because if anything it weakens. Similar reasons to C
E This isn't relevant to the assertion made regarding the prevalence of Lyme

Originally posted by dcummins on 12 Jul 2019, 18:02.
Last edited by dcummins on 13 Jul 2019, 15:31, edited 1 time in total.
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
Can someone explain question 6 please? e-Gmat, Magoosh?
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
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allahisgreat wrote:
Can someone explain question 6 please? e-Gmat, Magoosh?

Answered in detail here: https://gmatclub.com/forum/although-gen ... l#p2287273
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Re: Although genetic mutations in bacteria and viruses can lead to epidemi [#permalink]
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Thanks GMATNinja for the explanation. I would like to add to his explanation, albeit the contribution might be only feeble help if someone wants to understand it on lines of Critical Reasoning :)

Basically the author's conclusion is CAUSAL. (Increase in deer population ( associated with growth of Suburbs) led to prevelance of ticks in PARTS of US)
In any causal argument, there is always a correlation involved ( the cause and effect are positively correlated) and to strengthen the causal link we could ALWAYS weigh on the TIMING of either events ( basically sequence of these correlated events will help us understand the causality).

Now the argument presented by the author simply tells us that cause is => deer population increase ( associated with Growth of Suburbs)
But this SUBURB increase when did this happen? We don't know. When we consider Option A then we NOW know that compared to earlier times the deer pop increased ( or the SUBURBS increased) because both are ASSOCIATED ( considering premise is not false).

Hence Option A does not re-iterate the premise, it DEFINES the timeline of the cause and then we can say that in 19th Century the cause was not there, effect was also not there( sporadic spread) and NOW cause is there, so EFFECT is there(prevalent)

Option B, on the other hand, can be discarded because of the LIKELIHOOD of the outdoor is not decided by INTEREST. We can't really think statistically how an INTEREST to something relates to doing that thing maybe today, tomorrow ( there is equally likely chance that those sports might have started in 19th century itself or later with similar probability, mathematically speaking). Hence B can't provide a more lucrative support to the CAUSALITY.

I hope I have not added any information that might disrupt the concept of anyone. If so, kindly let me know :)

Regards,
Rishav
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