Carotenoids, a family of natural pigments, form an important part of

Question 2

Question 2 asks us which answer choice is most likely indicated by "a lack of bright coloration in a male" based on the idea that carotenoids are required for health.

The key to eliminating (A) is in the exact wording of the answer choice:

You are right that the passage mentions using carotenoids for detoxification processes, but what does it say about the efficiency of these processes? To answer this, look at the evidence stated in the passage:

This evidence tells us that some males have to use more carotenoids to boost their immune systems because they are more susceptible to disease and parasites. In other words, some males have to expend their carotenoids on immunity and detoxification because they are more likely to acquire a disease/parasite than other males.

What this does not tell us is how efficient the detoxification processes for either type of male is after they already acquired a disease/parasite. The drab males could have detoxification processes just as efficient as their flashy counterparts, but still use more carotenoids to boost their immunity because they are more susceptible to disease/parasites in the first place.

Because of the above reasoning, we cannot conclude that "a lack of bright coloration in a male is most likely to indicate" that those males have "inefficient detoxification processes." (A) is not the answer to question 2.

As you point out, the evidence in support of (C) is clear: the passage states that "males that are genetically resistant will use fewer carotenoids for fighting disease and will advertise this by using the pigments for flashy display instead." So, we can easily infer that a lack of bright coloration indicates "low genetic resistance to disease." (C) is the correct answer.
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Passage breakdown

In passages that are one, long paragraph, it can be helpful to split the passage up. In this explanation, the passage will be split into three sections:

• Section 1: from the start to “...if carotenoids were either rare or required for health.”
• Section 2: from “The conventional view is that…” to “...their inferior counterparts”
• Section 3: from “Although this may be true…” to the end of the passage.

In the first section, the author introduces an animal behavior and provides two potential reasons for that behavior.

• The behavior: "females prefer males with brighter carotenoid-based coloration."
• Two potential reasons for this behavior: carotenoids are either rare or required.

In the second section, the author outlines the conventional view.

• This view holds that carotenoids are meaningful because they are rare.

In the third section, the author argues that, while the conventional view may be true, the other potential explanation is ALSO true.

• The author states that "there is growing evidence that carotenoids are meaningful also because they are required."
• He/she then provides details to support this claim.

For more on the process of breaking down RC passages, check out this article and our live RC videos.

Explanations for individual questions

• Question 1
  
  • Part 1
  • Part 2
• Question 2
• Question 3
  
  • Part 1
  • Part 2
• Question 5
  
  • Part 1
  • Part 2

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Thanks for the upload.

Please comment on explanations, as I managed only to complete reading comprehension in 11:11.
Passage Analysis:
Tone: Explains / Descriptive
Organization:
Describe carotenoids usage in animals - 2 schools of thoughts [go the same way].

1. Inference:
The conventional view is that carotenoids are meaningful because they are rare: healthier males can forage for more of the pigments than can their inferior counterparts.
ANS: D possesses superior foraging capacity : healthier males can forage for more of the pigments than can their inferior counterparts.

2. Inference:
Although this may be true, there is growing evidence that carotenoids are meaningful also because they are required: they are used by the immune system and for detoxification processes that are important for maintaining health.
Males that are more susceptible to disease and parasites will have to use their carotenoids to boost their immune systems, whereas males that are genetically resistant will use fewer carotenoids for fighting disease and will advertise this by using the pigments for flashy display instead.
ANS: C Low genetic resistance to disease : males that are genetically resistant will use fewer carotenoids for fighting disease and will advertise this by using the pigments for flashy display instead.

3. Inference
Studies of several animal species have shown that when choosing mates, females prefer males with brighter carotenoid-based coloration.
ANS: E Fitness as a mate : Studies of several animal species have shown that when choosing mates, females prefer males with brighter carotenoid-based coloration.

4. Inference
Animals acquire carotenoids either directly (from the plants and algae that produce them) or indirectly (by eating insects) and store them in a variety of tissues.
ANS: A They do not produce carotenoids themselves (obtain via POE + insect = animal, therefore if these animals / insects obtained carotenoids from plants / insects, therefore these animals / insects cannot themselves produce carotenoids) - Experts please help on Q4

5. Inference
It may be that males can use scarce carotenoids either for immune defense and detoxification or for attracting females.
ANS: C They cannot be used simultaneously to brighten coloration : Because of the word OR

Kudos and constructive comments are appreciated. Thanks

Question 5 is the hardest one imo:

RC00423-05
5. Information in the passage suggests that which of the following is true of carotenoids that a male animal uses for detoxification processes?

(A) They were not acquired directly from plants and algae. carotenoids can be acquired from plants or insects and we don't have any info about whether there are different uses of the carotenoids from both sources
(B) They cannot be replenished through foraging. If animals use the sources mentioned above they can replenish carotenoids
(C) They cannot be used simultaneously to brighten coloration. This is mentioned in the passage. "It may be that males can use scarce carotenoids either for immune defense and detoxification or for attracting females". Yes, it says maybe, but it is the best out of all answers.
(D) They do not affect the animal's susceptibility to parasites. Carotenoids can be used to bolster the immune system, hence this answer is incorrect
(E) They increase the chances that the animal will be selected as a mate. It actually weakens the chances because carotenoids used for detoxification can't be used to increase brightness, leadiing to a higher chance of mating

HI GMATNinja , mikemcgarry , egmat , sayantanc2k, RonPurewal , DmitryFarber , MagooshExpert (Carolyn), ccooley , GMATNinjaTwo , SarahPurewal , EMPOWERgmatVerbal

Here is the relavent part but how to infer?

Animals acquire carotenoids either directly (from the plants and algae that produce them) or indirectly (by eating insects) and store them in a variety of tissues.

4. The passage implies which of the following about the insects from which animals acquire carotenoids?

(A) They do not produce carotenoids themselves.
(B) They use carotenoids primarily for coloration.
(C) They maintain constant levels of carotenoids in their tissues.
(D) They are unable to use carotenoids to boost their immune system.
(E) They are available in greater abundance than are carotenoid-bearing plants.
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I was thinking the same thing, but took clue from the information from within the brackets. Acquire directly (....that produce them) or indirectly (..eating insects). Infered that plants can produce them (animal consuming the plants that DIRECTLY produce carotenoids) and insects cannot produce carotenoids (animals acquiring carotenoids from insects, which in turn might be eating those plants, hence INDIRECTLY).

Await expert's view though.

GMATninja2 workout broall Gnpth
Can you please explain in q4 how it is inferred ?

Hi NandishSS

Though not an expert, I selected A as the answer based on the below



This may mean that insects acquire the cartenoids by feeding on plants or algae that produce them.So, insects do not produce themselves.

IMO Option A is the best which captures this.

HTH!

teaserbae

The answer lies in the following lines

"Animals acquire carotenoids either directly (from the plants and algae that produce them) or indirectly (by eating insects) and store them in a variety of tissues. "

Now what can we infer about the insects ?

Animals either acquire carotenoids from plant or by eating insects. These insects which come under the classification of animals again must have acquired carotenoids through plants or by eating some other insects. Hence these insects didnot produce the carotenoids themselves and that is what option A states.
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avvbh

"Studies of several animal species have shown that when choosing mates, females prefer males with brighter carotenoid-based coloration"

"Males that are genetically resistant will use fewer carotenoids for fighting disease and will advertise this by using the pigments for flashy display instead."

From the above 2 lines in the paragraph, inferring option E is not difficult.
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Main point - presence of C, reason for that, usefulness.

RC00423-01
resistant
1. According to the “conventional view” referred to in line 13 of the passage, brighter carotenoid-based coloration in certain species suggests that an individual

The conventional view is that carotenoids are meaningful because they are rare: healthier males can forage for more of the pigments than can their inferior counterparts

(D) possesses superior foraging capacity -

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RC00423-02
2. The idea that carotenoid-based coloration is significant partly because carotenoids are required for health suggests that a lack of bright coloration in a male is most likely to indicate which of the following?

they are used by the immune system and for detoxification processes that are important for maintaining health.

(A) Inefficient detoxification processes -
(C) Low genetic resistance to disease -

decider - males that are genetically resistant will use fewer carotenoids for fighting disease and will advertise this by using the pigments for flashy display instead.

C is better than A

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RC00423-03
3. The passage suggests that relatively bright carotenoid-based coloration is a signal of which of the following characteristics in males of certain animal species?

healthier males can forage for more of the pigments than can their inferior counterparts

was confused in following choices.

(A) Readiness for mating behavior - urgency
(E) Fitness as a mate - better choice.

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RC00423-04
4. The passage implies which of the following about the insects from which animals acquire carotenoids?
or indirectly (by eating insects)
(A) They do not produce carotenoids themselves. - indirectly

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RC00423-05
5. Information in the passage suggests that which of the following is true of carotenoids that a male animal uses for detoxification processes?

It may be that males can use scarce carotenoids either for immune defense and detoxification or for attracting females.

(C) They cannot be used simultaneously to brighten coloration.
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Hi NandishSS aplogies for my late reply

the answer to your question lies in the sentence below.

Animals acquire carotenoids either directly (from the plants and algae that produce them) or indirectly (by eating insects) and store them in a variety of tissues.


notice that animals get carotenoids DIRECTLY from plants ( from here you can infer that plants are carriers of carotenoids . i.e . plants produce carotenoids themselves ) OR Animals can get carotenoids INDIRECTLY from insects (from this part of sentence you can infer that insects ARE NOT CARRIERS of carotenoids. i.e. insects dont produce carotenoids themselves)

hence, (A) is correct answer

Hi GMATNinja,

I was wondering could you please explain why option A is incorrect for Q2? The passage states that carotenoids are used "by the immune system for detoxification processes". It is also given that "males can use scarce carotenoids either for immune defense and detoxification or for attracting females". Based on this, can't we infer that a lack of bright coloration means that the carotenoids were used by the immune system or rather the detoxification was inefficient? I understand why option C is correct because we are strictly told about this option in the last line of our paragraph; however, I am unable to see the true reasoning behind why option A is incorrect.

If you could please share your thoughts behind it, I would immensely appreciate it!

I understand that C is the best answer for Q.4 as mentioned in line 21-23, "It may be that males can use scarce carotenoids either for immune defense and detoxification or for attracting females."

But I still curious about it.

Line 26-28, "...males that are genetically resistant will use fewer carotenoids for fighting disease and will advertise this by using the pigments for flashy display instead."

This sentence clearly implied that the carotenoids can be used for fighting disease (detoxification) and attracting females simultaneously.
Or maybe it's about my mistaken interpretation.

Any expert, please help clarify my doubts.
Thank you in advance.

The OA for question 4 is (A).

Did you mean to ask about question 2? If so, please check out this post and let us know if you have any further questions.

I hope that helps!
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My bad. I was asking about Q.5, not 4.
Anyway, I followed your attached link and read your post. It seems like that unlike the healthy males, weak males cannot use carotenoids for two purposes at the same time.
Am I right?

Posted from my mobile device

Take another look at the exact wording of question #5:

This question is asking specifically about "carotenoids that a male animal uses for detoxification processes." So, we know that the exact carotenoids in question have already been allocated for detoxification.

Out of all of the carotenoids that a given male bird can scrounge up, he will use some amount for his immune system/detoxification and some amount for coloration. A bird that is "more susceptible to disease and parasites" has to use his carotenoids to boost his immune system, while a more resistant bird will use "fewer carotenoids for fighting disease and will advertise this by using the pigments for flashy display instead."

In either case, if a carotenoid has already been used for detoxification processes, that exact carotenoid cannot also be used to brighten the bird's coloration. This is true for both healthy and unhealthy birds. So, carotenoids that a male animal uses for detoxification processes "cannot be used simultaneously to brighten coloration." (C) is the correct answer for question #5.

I hope that helps!
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Dear GMATNinja

I struggle between D and E, I chose D because the statement ""
Does not it imply that recovered from carotenoids?


Please help.

Bright carotenoid-based coloration might indicate a strong immune system and, thus, an ability to recover well from a parasite infestation. But bright carotenoid-based coloration does NOT indicate that the animal IS recovering from parasite infestation. The coloration is a sign that the male is fit as a mate, not that the male is actively recovering from an illness or infection.

In other words, you cannot point to male with bright carotenoid-based coloration and say, "oh, that male must be recovering from a parasite infestation right now."

I hope that helps!
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