HOT Competition: Bacteria and archaea, collectively known as prokaryot

Question

Bacteria and archaea, collectively known as prokaryotes, are present on every continent and make up around half of global biomass -- the total weight of all organisms on Earth. Most prokaryotes perform respiration that uses energy and releases carbon dioxide, contributing to climate warming. Therefore, as global temperatures rise, prokaryotes could increase climate warming at a faster rate than current models suggest.

Which of the following would it be most useful to know in order to evaluate the argument?

A. The relationship between temperature and the prokaryote’s carbon output is inversely proportional

B. The amount of carbon dioxide released by a prokaryote in a given period of time depends on its weight.

C. The carbon output of the prokaryote during a given time period depends on its respiration rate, which is positively correlated to changes in temperature.

D. Some prokaryotes will increase their carbon output in response to higher temperatures.

E. The relationship between temperature and the prokaryote’s respiration rate is inversely proportional

Bunuel · Accepted Answer

GMATWhiz Explanation

Step 1 – Analysing the stimulus and question stem

Bacteria and archaea, collectively known as prokaryotes, are present on every continent and make up around half of global biomass -- the total weight of all organisms on Earth. 
 • Bacteria and archaea – together known as prokaryotes.
• They are found on every continent.
• They comprise half of the total weight of all organisms living on the earth.

Most prokaryotes perform respiration that uses energy and releases carbon dioxide, contributing to climate warming. 
 • Majority of the prokaryotes display respiration.
• Respiration takes in energy and gives out carbon dioxide.
• Such respiration adds to climate warming.
 o  Inference : Carbon dioxide released into the atmosphere adds to climate warming.

Therefore, as global temperatures rise, prokaryotes could increase climate warming at a faster rate than current models suggest.
 •  Conclusion : With temperatures rising globally, climate warming could also increase at a faster speed than that indicated by current models. And prokaryotes would be responsible for this increase at a faster speed.

Step 2 – Pre-thinking

1. The conclusion to be evaluated is - . prokaryotes could increase climate warming at a faster rate than currently believed. Why? The conclusion contains information about “rising global temperatures”. Thus, the “rising temperatures” and “faster rate of increase in climate warming” are definitely correlated. And if the “prokaryotes” are somehow responsible for upping the climate warming rate, then, the prokaryotes and the “rising temperatures” must also be correlated.

2.  Missing link 
 a. We know the respiration carried out by the prokaryotes adds to climate warming by adding carbon dioxide to the air. 
b. Perhaps faster respiration = more carbon dioxide = faster climate warming. For that to be true, we need to know two things?
 i.  Evaluate question:  
 1. Whether respiration rate increases with increase in global temperatures?
2. Whether the amount of carbon dioxide released increases with an increase in the respiration rate ?

Step 3 – Answer Choice Elimination

Option A Analysis 
“Inversely proportional” means if one entity increases by a certain amount, then the other entity decreases by that same amount. So, if the temperature increases then the carbon output decreases. That should lead to less addition to climate warming and that cannot certainly lead to a faster rate of climate warming. This choice actually casts a doubt on the conclusion. 
Incorrect Choice.

Option B Analysis 
The prokaryotes make up half the biomass weight. Thus, the carbon dioxide realesed would be according to that at any given point. This does not explain why the climate warming rate would be faster. The total weight of the prokaryotes is not changing here. This choice is just a distortion of the given information.
Incorrect Choice.

Option C Analysis 
“Positively correlated” means if one entity increases, the other entity also increases. 
Per this choice, 
 • Increase in temperature = increase in respiration rate
 o And 
• increase in respiration rate = increase in carbon output. 
This choice is the answer to both the evaluate questions that we framed during pre-thinking. This choice would make us believe more in the conclusion.
Correct Choice.

Option D Analysis 
“Some” could be a very small number or could be a huge number – anything from 1-99 in a population of 100. Thus, the impact of this choice will be ambiguous. Too small a number then, the choice does not make us believe more in the conclusion. Only a high number would do that. Because of the ambiguous impact, this choice has to be ruled out.
Incorrect Choice.

Option E Analysis 
If the temperature increases then the respiration rate decreases. Ideally, although we do not know, a decrease in respiration rate should lead to a decrease in the amount of carbon dioxide released. That should lead to less addition to climate warming and that cannot certainly lead to a faster rate of climate warming. This choice actually casts a doubt on the conclusion. 
Incorrect Choice.

chaitralirr · Answer

Bacteria and archaea, collectively known as prokaryotes, are present on every continent and make up around half of global biomass -- the total weight of all organisms on Earth. Most prokaryotes perform respiration that uses energy and releases carbon dioxide, contributing to climate warming. Therefore, as global temperatures rise, prokaryotes could increase climate warming at a faster rate than current models suggest.

Stimulus: Bacteria and archea collectively known as prokaryotes are present on every continent and make up around half of global mass. The total weight of all organisms on earth. Most prokaryotes perform respiration that uses energy and releases carbon-dioxide contributing to climate warming therefore the global temperature rise prokaryotes could increase climate at a faster rate than current suggested model

Which of the following would it be most useful to know in order to evaluate the argument?

We will need to understand the how will the prokaryotes the respiration rate/carbon output in response to temperature rise

A. The relationship between temperature and the prokaryote’s carbon output is inversely proportional  this will not speed up global warming

B. The amount of carbon dioxide released by a prokaryote in a given period of time depends on its weight.  irrelevant

C. The carbon output of the prokaryote during a given time period depends on its respiration rate, which is positively correlated to changes in temperature.  Correct

D. Some prokaryotes will increase their carbon output in response to higher temperatures.  by using some we will not be able to evaluate the impact

E. The relationship between temperature and the prokaryote’s respiration rate is inversely proportional  will not impact

IMO C

yashikaaggarwal · Answer

Mod Posts do not count

Concluding statement: as global temperatures rise, prokaryotes could increase climate warming at a faster rate than current models suggest. The prokaryotes are said to use energy and releases carbon dioxide, by performing respiration that contributes to climate warming. The most effective evaluation to evaluate the argument is : A. The relationship between temperature and the prokaryote’s carbon output is inversely proportional (if the relation is inversely proportional how the statement will evaluate the argument in the passage? There has to be a positive relation between two to testify the passage) (Incorrect) B. The amount of carbon dioxide released by a prokaryote in a given period of time depends on its weight. (No such parameter is given to determine the amount of carbon released proportional to weight of prokaryotes) (Incorrect) C. The carbon output of the prokaryote during a given time period depends on its respiration rate, which is positively correlated to changes in temperature.(Yes, the respiration rate of prokaryote is been considered as a major factor in determining the carbon output in the climate) (Correct) D. Some prokaryotes will increase their carbon output in response to higher temperatures.(No factor to determine That the carbon is released due to high temperature of climate While it's the other way round) (Incorrect) E. The relationship between temperature and the prokaryote’s respiration rate is inversely proportional(No, the carbon release of prokaryote and temperature rising are directly proportional, as given in passage) (Incorrect) IMO C Posted from my mobile device

Varunsawhney8 · Answer

Bacteria and archaea, collectively known as prokaryotes, are present on every continent and make up around half of global biomass -- the total weight of all organisms on Earth. Most prokaryotes perform respiration that uses energy and releases carbon dioxide, contributing to climate warming. Therefore, as global temperatures rise, prokaryotes could increase climate warming at a faster rate than current models suggest.

Which of the following would it be most useful to know in order to evaluate the argument?

Best Guess is C

A. The relationship between temperature and the prokaryote’s carbon output is inversely proportional
Irrelevant 
We are not provided with any information of such relationship 
Incorrect

B. The amount of carbon dioxide released by a prokaryote in a given period of time depends on its weight.
Irrelevant 
We are not concerned with weight if there was some reasoning for weight and temperature relation causing inc in releasing of CO2 then the option was worth trying
Incorrect

C. The carbon output of the prokaryote during a given time period depends on its respiration rate, which is positively correlated to changes in temperature.
This choice is something related to the gap leading to the conclusion of the argument
Hold this choice

D. Some prokaryotes will increase their carbon output in response to higher temperatures.
Presence of Some is problem
Incorrect

E. The relationship between temperature and the prokaryote’s respiration rate is inversely proportional
If the rel. is inverse then concl. will not be true.
Incorrect

GmatDisciple · Answer

Q. type: Evaluation.

Conclusion: as temperatures rise, prokaryotes could increase CO_2 production
Missing info: Correlation between temperatures and prokaryotes' CO_2 production

A: Would lead to opposite of conclusion
B: out of scope
C:  Winner 
D: Warped: Some could mean even 1 or 2 species and certainly does not imply all.
E: Similar to A would lead to opposite of conclusion

piyush0122 · Answer

Bacteria and archaea, collectively known as prokaryotes, are present on every continent and make up around half of global biomass -- the total weight of all organisms on Earth. Most prokaryotes perform respiration that uses energy and releases carbon dioxide, contributing to climate warming. Therefore, as global temperatures rise, prokaryotes could increase climate warming at a faster rate than current models suggest.

Which of the following would it be most useful to know in order to evaluate the argument?

A. The relationship between temperature and the prokaryote’s carbon output is inversely proportional- if this relationship is true then it will have an opposite effect of what the author has stated.

B. The amount of carbon dioxide released by a prokaryote in a given period of time depends on its weight.-as the weight of prokaryotes remains same then there will be no increase in temperature attributed to prokaryotes.

C. The carbon output of the prokaryote during a given time period depends on its respiration rate, which is positively correlated to changes in temperature.- correct choice because if carbon output depends on rate of respiration, which in turn is directly proportional to temperature then with increase in temperature rate of respiration will increase and as a result of which the carbon output will increase. so answering yes to the statement strengthens the argument and answering no the the statement weakens the argument. hence, correct choice.

D. Some prokaryotes will increase their carbon output in response to higher temperatures.- incorrect choice because this is not enough to evaluate the argument and choice C is a better choice.

E. The relationship between temperature and the prokaryote’s respiration rate is inversely proportional- this will have an opposite effect of the intended effect.

raghav2512 · Answer

The conclusion is:
as global temperatures rise, prokaryotes could increase climate warming at a faster rate than current models suggest.

A. The relationship between temperature and the prokaryote’s carbon output is inversely proportional
-- If it is inversely proportional it will not increase the temperature at a faster rate. But, if it is not inversely proportional, let's say remains the same, in that case there's no impact. So gone

B. The amount of carbon dioxide released by a prokaryote in a given period of time depends on its weight.
--This will not impact the climate warming at all

C. The carbon output of the prokaryote during a given time period depends on its respiration rate, which is positively correlated to changes in temperature.
--If the respiration is positively correlated and as respiration will increase warming through carbon emissions, it will increase warming at a faster rate. But, if it is not positively correlated, it will not increase the temperature at a faster rate. Looks C

D. Some prokaryotes will increase their carbon output in response to higher temperatures.
--If only talks about some.What about others? Gone

E. The relationship between temperature and the prokaryote’s respiration rate is inversely proportional
--If the respiration rate is inversely proportional,it will not increase temperature at a faster rate. Infact it will decrease it. But, if it is not inversely proportional, we don't know for sure whether the temperature will increase or not. Maybe it remains the same.This option comes close. But I'll stick with C

IMO C

Posted from my mobile device

amlanbanerjee · Answer

IMO Correct option is C
In Evaluate Question we need to look for answer choice whose Extremity (True or False) determines the fate of the Conclusion i.e whether the conclusion stands a leg
Here the structure of the argument is as follows:

Respiration of prokaryotes releases Carbon Di Oxide (co2)(CAUSE 1 )-> C02 increases global temperature(EFFECT 1)
Conclusion: As global temperature rises >(cause 2 ) prokaryotes will contribute to faster rate than predicted . (Effect 2 )
Looking closely Effect 1= Cause 2 
So we can structure the argument like this : Cause 1 -> Effect 1->Effect 2 .We can see that a Circular Loop must be true for the conclusion to hold true. So our target will be to find an anser choice that confirms this circular loop

A. The relationship between temperature and the prokaryote’s carbon output is inversely proportional-  INCORRECT 
 Ask Yes Or No to the answer choice : If Yes the conclusion breaks but If No The conclusion has no effect . Note :  NOT inversely proportional  does not equals to  Positively proportional .

B. The amount of carbon dioxide released by a prokaryote in a given period of time depends on its weight.  Incorrect 
 (Out Of Scope as it is not aligned with our Pre Thinking )

C. The carbon output of the prokaryote during a given time period depends on its respiration rate, which is positively correlated to changes in temperature.

Correct as it is aligned with our Pre thinking  . 
Ask YES or NO . Both the answers revolves around the EXTREMITY of the conclusion

D. Some prokaryotes will increase their carbon output in response to higher temperatures.  Incorrect  
 Modifier Some means 1 % to 99% and so this Answer Choice is Not strong . If only 1% does the work the conclusion will not be true but the conclusion is true if 99% does the work

E. The relationship between temperature and the prokaryote’s respiration rate is inversely proportional .  Incorrect  
( Same error AS in A )

kartickdey · Answer

Bunuel ,  bb  I could not understand the logic. The question stem is about evaluation. So it could be either a strengthener or a weakened. I was confused between A and C. A has been eliminated as it weakens the argument but one weakener may qualify as a evaluatory statement. Please help.

guddo · Answer

Prokaryotes make up about half of Earth's biomass and release CO2 through respiration, contributing to climate warming. The argument concludes that rising global temperatures could cause prokaryotes to accelerate warming more than current models predict.

The argument assumes that higher temperatures lead to increased respiration rates (and thus greater CO2 output) from prokaryotes. To evaluate this, it is most useful to know whether respiration rate is positively correlated with temperature, as this directly impacts whether prokaryotes will release more CO2 as temperatures rise.

Answer: C

guddo · Answer

Let me try.

The argument concludes that higher temperatures will cause prokaryotes to release more CO2, worsening warming. This assumes that higher temperatures increase prokaryotes' respiration rate (which produces CO2).

Option C asks whether respiration rate is positively correlated with temperature. If yes, the argument is strong; if no, the argument is weak. This is the crucial test.

Option A only states an inverse relationship. If true, it weakens the argument. If false, it doesn't prove a positive link, respiration might be unaffected by temperature. Thus, it doesn't provide the two-way test needed for evaluation.

Therefore, C is correct.

kartickdey · Answer

as you have said if option A is false, then it would not affect the respiration. So Procaryotes would not increase climate warming. So it weakens the argument and it passes the two way test.

egmat · Answer

Option A claims:  Higher temperature →  LESS  carbon output (inverse relationship)

Think about it:
• If A is  TRUE  → Higher temps mean  less  CO2. This would actually  DESTROY the argument  
• If A is  FALSE  → The relationship is "not inverse"- but that could mean  anything : no relationship, positive relationship, negative relationship, but not proportional or something else

This is the key insight:  Negating "inversely proportional" doesn't automatically give you "positively proportional."  It just gives you "NOT inversely proportional."   It could also mean that higher temps mean less CO2, but NOT in a proportional fashion.    That also weakens the argument

Why C is the correct answer:

The argument needs a specific mechanism: Rising temperature → More CO2 release

C provides exactly this:  Temperature ↑ → Respiration rate ↑ → Carbon output ↑

If you negate C: No positive correlation between temperature and respiration → The whole argument falls apart. There's no reason to expect accelerated warming.

The difference: 
• A being false: "Maybe there's a positive relationship, maybe not" → Argument might work, might not
• C being false: "There's definitely NOT a positive relationship" → Argument  definitely  fails

C is the necessary assumption because the argument absolutely requires that positive link to exist.

Hope this creates clarity!

arushi118 · Answer

Hello,
I have a doubt - that the question is about "evaluating" the argument, and not strengthening or weakening it. So if A is true then the argument will be weakened and if the statement A is false then the argument will be strenthened. Can you please point out the flaw in my reasoning as to why can A not be correct. Thankyou in advance.

KarishmaB ,  Bunuel

miag · Answer

Hi,

Let me try to help out with this one: 
This is an evaluation question, so we're looking for the answer that most directly tests the key assumption of the argument.
The argument assumes that as temperature rises, prokaryotes will release more CO2. So the most useful thing to know is whether higher temperatures actually increase their respiration (and therefore carbon output).
Choice A only tells us one extreme possibility (inverse relationship). While it could weaken the argument if true, it doesn't directly test the core mechanism linking temperature to increased carbon output.
Choice C directly addresses that mechanism, it tells us whether carbon output increases as temperature rises. That's why C is more useful for evaluating the argument.

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HOT Competition: Bacteria and archaea, collectively known as prokaryot

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

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