The quality of heliotropism, a plant's ability to change its bearing

Question

The quality of heliotropism, a plant's ability to change its bearing to face the direction of the sun, is common in sunflowers. Moss displays the tendency to grow only on the side of trees opposite the most sunny direction. Therefore, moss exhibits the opposite phenomenon of heliotropism, which may be called contra-heliotropism.

The argument is flawed primarily because the author

The argument is flawed primarily because the author

A. does not take into consideration the fact that the direction of the sun changes during the day and between the southern and northern hemispheres

B. includes sunflowers and moss in the same group while ignoring obvious differences between them

C. creates a new word in Latin which does not really exist

D. fails to distinguish between a plant's special ability and a plant's special growth conditions

E. compares two types of plants which rarely grow in similar conditions

Bunuel · Accepted Answer

OFFICIAL EXPLANATION

The quality of heliotropism, a plant's ability to change its bearing to face the direction of the sun, is common in sunflowers. Moss displays the tendency to grow only on the side of trees opposite the most sunny direction. Therefore, moss exhibits the opposite phenomenon of heliotropism, which may be called contra-heliotropism.

The argument is flawed primarily because the author

The argument is flawed primarily because the author

A. does not take into consideration the fact that the direction of the sun changes during the day and between the southern and northern hemispheres

Incorrect.

This is an Argument Flaw question. You are required to locate the inherent flaw in the argument's conclusion or its underlying assumption. In this argument, sentences 1 and 2 are premises, citing facts. Sentence 3 is the conclusion, as it begins with the conjunction Therefore:

Premise A: some plants, like sunflowers, can change direction (bearing) to face the sun. This is called heliotropism.
 + 
Premise B: moss grows on the least sunny side of trees
 ≠
Conclusion: moss exhibits the opposite of heliotropism

By using the word direction, it appears that the author did take into consideration the movement of the sun. Otherwise, the author would say that sunflowers grow facing "the sun" and that mold grows on the side "opposite the sun".

Try to figure out what sort of connection the author suggests exists between the premises; then look for an answer choice that embodies the flaw in that suggested connection.

B. includes sunflowers and moss in the same group while ignoring obvious differences between them

Incorrect.

The conclusion of the argument does not include sunflowers and moss in the same group. Rather, it ties them in a relationship of opposition, claiming that moss exhibits a phenomenon which is the exact opposite of the phenomenon exhibited by sunflowers.

C. creates a new word in Latin which does not really exist

Incorrect.

In order to locate the flaw in the author's argument, we must focus on the conclusion and the way it connects the premises to each other. The conclusion in this argument is that moss exhibits the opposite phenomenon of heliotropism. The author then suggests the word contra-heliotropism to refer to the phenomenon exhibited by moss. However, this suggestion does not constitute a flaw in the way the author ties the premises in a relationship of opposition.

D. fails to distinguish between a plant's special ability and a plant's special growth conditions

The author suggests a relationship of opposition between two unrelated phenomena: one is the sunflowers' special ability to follow the sun in the sky, and the other is moss' tendency to grow on the least sunny side of trees, a tendency stemming from the moss' required growth conditions. The author does not seem to tell the two apart.

E. compares two types of plants which rarely grow in similar conditions

Incorrect.

This is an Argument Flaw question. You are required to locate the inherent flaw in the argument's conclusion or its underlying assumption. In this argument, sentences 1 and 2 are premises, citing facts. Sentence 3 is the conclusion, as it begins with the conjunction Therefore:

Premise A: some plants, like sunflowers, can change direction (bearing) to face the sun. This is called heliotropism.
 + 
Premise B: moss grows on the least sunny side of trees
 ≠
Conclusion: moss exhibits the opposite of heliotropism

We can see that the correlation suggested by the author is not between two plants, but between two phenomena - one is an ability possessed by sunflowers and the other is the tendency of moss to grow in particular places. Furthermore, the author does not compare the two but contrasts them, suggesting a relationship of opposition.

Anisha1637 · Answer

IMO D because we can clearly see that the sunflower has the ability to face the sun but not grow whereas the author is talking about moss' growth ability and not its feature. The comparison is not parallel.

winterschool · Answer

The quality of heliotropism, a plant's ability to change its bearing to face the direction of the sun, is common in sunflowers. Moss displays the tendency to grow only on the side of trees opposite the most sunny direction. Therefore, moss exhibits the opposite phenomenon of heliotropism, which may be called contra-heliotropism.

The argument is flawed primarily because the author

The argument is flawed primarily because the author

A. does not take into consideration the fact that the direction of the sun changes during the day and between the southern and northern hemispheres  Irrelevant

B. includes sunflowers and moss in the same group while ignoring obvious differences between them  Incorrect

authors doesnt say about this

C. creates a new word in Latin which does not really exist  Incorrect

this cant be a flaw

D.  fails to distinguish between a plant's special ability and a plant's special growth conditions   Correct

authors compare ability with growth condition

E. compares two types of plants which rarely grow in similar conditions  Incorrect

author doesnt compare between two types of plants

mSKR · Answer

The quality of heliotropism, a plant's ability to change its bearing to face the direction of the sun, is common in sunflowers. Moss displays the tendency to grow only on the side of trees opposite the most sunny direction. Therefore, moss exhibits the opposite phenomenon of heliotropism, which may be called contra-heliotropism.

The argument is flawed primarily because the author

The argument is flawed primarily because the author

the key flaw is: he compares wrong elements

A. does not take into consideration the fact that the direction of the sun changes during the day and between the southern and northern hemispheres
even sun direction changes, it is not the key flaw. the key flaw is he compares wrong elements based on wrong criterias.
B. includes sunflowers and moss  in the same group  while ignoring obvious differences between them
not mentioned
C. creates  a new word  in Latin which does not really exist
irrelevant
D.  fails to distinguish  between a plant's special ability and a plant's special growth conditions
author distinguishes plant's special ability vs plant;s growth conditions

E. compares two types of plants which rarely grow in similar conditions 
compares wrong groups of flowers.

I will mark E as the answer

mSKR · Answer

Hi  IanStewart   Maxximus

Can you please check the wordings are correct or my understanding is wrong of the statement:

In the argument, author already distinguish/different between plant's special ability and plant's special growth conditions
The key flaw is : it compares wrong phenomenon/not valid elements to compare.

is the flaw it doesn't distinghuish between elements?
But , I can see the differences in the argument memtioned.

please comment on the understanding of option D

Thanks!  IanStewart   Maxximus

Bhu750 · Answer

Hi,

I am not an expert.. but this is what I think..

Option D - fails to distinguish between a plant's special ability and a plant's special growth conditions
The author is comparing 2 incomparable situations - a special ability vs growth condition. He points out an invalid distinction. 
So the option states that by comparing 2 incomparable conditions - he fails to distinguish the 2  for the correct reasons . Hence that's the answer.

Also why option E is incorrect,
compares two types of plants which rarely grow in similar conditions.. they might grow in the same soil, same temperature.
The sunflower facing the sun is a special ability that differs from growth of the sunflower as such.
(Option E does the same mistake as the author)

mSKR · Answer

Thanks for the feedback.

But as per the question , don't we need to find a flaw in argument . The argument flaw is : author compares wrong categories.

E option says: compare 2 plants --this is the flaw.
D says : doesn't distinguish between 2 plants ( D option doesn't say distinguish between CATEGORIES/phenomena). Is this the flaw that he didn't distinguish between plants? We can already deduce differencec between these plants.

I just want to make sure : Is D correct in wording or my understanding is wrong of the meaning of D.

AndrewN   IanStewart  : please share your opinion on meaning of D .

Thanks!

IanStewart · Answer

It's a prep company question, so it's really not worthwhile expending a lot of effort trying to understand what it means. Official questions use language in a very precise way. Prep company questions are usually cavalier about word choice and sentence structure, and that's true of this question.

The question is trying to say: Sunflowers are able to turn towards the sun. That ability is called 'heliotropism'. Moss grows on trees away from the sun. So moss has the opposite ability, something we could call "contra-heliotropism".

That argument confuses two things. If you stick a sunflower in the ground somewhere, and the sun comes out from behind the clouds, the sunflower will move in the direction of the sun. But if you stick a tree with moss on it somewhere, and the sun comes out, the moss doesn't move around to the other side of the tree. Moss doesn't have any 'special ability', as far as moving towards or away from the sun goes. It's just that moss grows in the dark, not in the light. So that's why D is right.

AndrewN · Answer

Hello,  mSKR . I agree with the interpretation  IanStewart  provided above. Moreover, answer choice (C) is one of the most bizarre—clearly non-official—options I have ever seen. Are we supposed to know the entirety of the Latin lexicon to qualify whether  contra-heliotropism  is a legitimate word? The restrictive use of  which  in that answer choice and in (E) points to a source that is less likely American and thus equally unlikely to show up as is on the GMAT™. Do not get me wrong, I enjoy exploring new questions, and I even write some from time to time, but sometimes straying from official questions can, in fact, be more trouble than it is worth.

- Andrew

IanStewart · Answer

Making answer C even more bizarre, "Helios" quite famously comes from Greek originally, not from Latin, though it did find its way into some Latin words eventually. And "contra-heliotropism" is a new word in English if it's a new word in any language -- the suffix "-ism" is not a Latin suffix (if the word were Latin, it might end in "-ismus", but not "-ism"). It's also unclear to me how answer C could ever be the right answer to a "what is wrong with the argument" question. There's no logical problem with coining new words. So I agree, one of the strangest answer choices I've seen!

The quality of heliotropism, a plant's ability to change its bearing

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The quality of heliotropism, a plant's ability to change its bearing

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