GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 24 Aug 2019, 19:41

Close

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

Of the many organisms found in marine ecosystems, sea otters play a un

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Find Similar Topics 
Manager
Manager
User avatar
B
Joined: 23 Sep 2013
Posts: 130
Concentration: Strategy, Marketing
WE: Engineering (Computer Software)
Reviews Badge
Of the many organisms found in marine ecosystems, sea otters play a un  [#permalink]

Show Tags

New post Updated on: 21 Jul 2019, 23:22
2
Question 1
00:00
A
B
C
D
E

based on 126 sessions

7% (02:15) correct 93% (02:43) wrong

HideShow timer Statistics

Question 2
00:00
A
B
C
D
E

based on 130 sessions

79% (00:34) correct 21% (00:46) wrong

HideShow timer Statistics

Question 3
00:00
A
B
C
D
E

based on 130 sessions

93% (00:26) correct 7% (00:30) wrong

HideShow timer Statistics

Question 4
00:00
A
B
C
D
E

based on 132 sessions

59% (01:10) correct 41% (01:41) wrong

HideShow timer Statistics

Question 5
00:00
A
B
C
D
E

based on 132 sessions

86% (01:10) correct 14% (01:08) wrong

HideShow timer Statistics

New Project RC Butler 2019 - Practice 2 RC Passages Everyday
Passage # 215, Date : 19-Jul-2019
This post is a part of New Project RC Butler 2019. Click here for Details


Of the many organisms found in marine ecosystems, sea otters play a uniquely significant role in maintaining their environments. Sea otters (Enhydra lutris) are a keystone species, a species whose effect on their environment is disproportionately great relative to their size in numbers or weight. Keystone species keep the growth of populations of other species in check and are thereby a determining factor of the type and number of other species in a community; keystone species are so named because their role is analogous to that of a keystone in an arch: while keystones bear the least amount of pressure among the components of an arch, the arch collapses without them.

The sea otter's reputation as a keystone species is largely a consequence of its affinity for sea urchins. Sea otters are known to prey upon over 100 different species, but the bulk of their diet consists of sea urchins and other marine invertebrates. Sea urchins are such highly preferred prey that sea otters have been known to significantly deplete urchin populations. In marine ecosystems at equilibrium, however, sea otters are often the primary force that keeps populations of sea urchins in check. Without sea otters, sea urchins and other seafloor herbivores would graze on help holdfasts, causing kelp to drift away from their substrates and die. The aggregate result of many such events leads to the destruction of entire kelp beds, resulting in a loss of habitat and nutrients for other organisms in the ecosystem. The extended consequences include local extinction of other species and vast urchin barrens: subtidal areas where the unchecked population growth of sea urchins has caused a dearth of kelp and, therefore, other marine species.

This ecological cascade effect of secondary extinctions resulting from a decrease in otter populations and corresponding growth in urchin populations was observed throughout the 19th century along the Pacific coast of North America. Sea otters had been aggressively hunted for their rich pelts since before the 1600s, and this practice was not outlawed until an international treaty was signed in 1911 to prevent further exploitation. Prior to the enforcement of the treaty, hunters caused sea otter populations to decline; this in turn caused sea urchin populations to explode. Consequently, the urchin populations overexploited their primary food source, kelp, creating a preponderance of urchin barrens.


1. The author's tone towards sea otters could best be described as

(A) disdainful
(B) dispassionate
(C) concerned
(D) critical
(E) jovial

Spoiler: :: OE
The primary purpose of this passage is to highlight the significance of the sea otter in its environment, and the first paragraph spends multiple sentences noting the meaning of keystone species to give a phrase to this importance.

The Sea Otter as a Keystone Species is an apt summary of the passage, and thus E is the correct answer.

Answer choice A is incorrect, as the prominence of the sea urchin in this passage is mitigated by the impact that the otter also has on kelp beds and other features of the ecosystem.

Answer choice D is similarly incorrect, as the urchins are one facet of the otter's importance; D fails to mention the otter at all.

Choices B and C are each too broad in scope, as this passage deals specifically with the sea otter; those answer choices seek to describe entire ecological topics in much too broad a scope.


2. Which of the following would be the most likely title for this passage?

(A) The Sea Otter and the Sea Urchin
(B) Ecological Cascade Effects in Global Ecosystems
(C) Marine Holdfasts: The Key to Biodiversity
(D) A Study of Urchin Barrens
(E) The Sea Otter as a Keystone Species

Spoiler: :: OE
Correct Answer: D

The first paragraph of the passage introduces sea otters and describes their role as a keystone species; the second details the effect that sea otters have in two types of populations, and the third demonstrates the effect that the otters have had on human society.

Thus, the passage as a whole is written to explain the significance of sea otters, which is the point of answer choice D.

While choices B, C, and E are each touched upon in the passage, each is done to support the overall significance of sea otters, and none is the primary focus of the passage.

Answer choice A is farther out of scope; the passage is descriptive in nature, making the verb advocate incorrect, and the passage only describes the effect of otters on the sea urchins, but does not talk about any type of strategy for doing so.


3. The primary purpose of this passage is to

(A) advocate a strategy for keeping sea urchins in check.
(B) explain the absence of kelp in the North American Pacific coast.
(C) outline the dietary habits of sea otters.
(D) describe the significance of sea otters in their ecosystems.
(E) define the term "keystone species."

Spoiler: :: OE
Correct Answer: B

The term holdfast is used in the second paragraph: Without sea otters, sea urchins and other seafloor herbivores would graze on kelp holdfasts, causing kelp to drift away from their substrates and die.

The effect of sea urchins and other herbivores on these holdfasts would be to permit kelp to drift away; thus, it can be inferred that without interference from herbivores, the role of the holdfast is to anchor the kelp, and B is the correct answer.

Answer choice A is incorrect as the kelps is the organism, not the holdfast itself.

Choices C, D, and E are unsupported by the passage.


4. Based on the information in the passage, what is the most likely meaning of holdfast?

(A) organisms that dwell at the lowest level of a body of water
(B) a root-like structure that anchors an organism
(C) aquatic arthropods that live in marine environments
(D) rocks used by sea otters to dislodge prey and open shells
(E) the act of embracing feverishly


5. According to the passage, which of the following could be most reasonably inferred about kelp?

(A) Kelp forests provide a unique habitat for a variety of marine organisms.
(B) Kelp is an important food source for coastal Californians.
(C) Kelp forests occur worldwide throughout temperate and polar coastal oceans.
(D) Kelp is an important part of the sea otter's diet.
(E) A 1911 treaty reinvigorated kelp forests by requiring otter hunters to plant marine algae.
Spoiler: :: OE
Correct Answer: A

The final sentence of the second paragraph states that: The extended consequences include local extinction of other species and vast urchin barrens: subtidal areas where the unchecked population growth of sea urchins has caused a dearth of kelp and, therefore, other marine species.

This sentence sets the cause and effect relationship that the lack of kelp led to the lack of other marine species.

Thus, it can be inferred that kelp provide a unique habitat for such species that were unable to survive in the absence of kelp.


Originally posted by solitaryreaper on 25 Sep 2014, 10:17.
Last edited by SajjadAhmad on 21 Jul 2019, 23:22, edited 4 times in total.
Updated.
Intern
Intern
avatar
B
Joined: 31 Jul 2013
Posts: 8
Location: India
Concentration: Technology, International Business
WE: Information Technology (Computer Software)
Reviews Badge
Re: Of the many organisms found in marine ecosystems, sea otters play a un  [#permalink]

Show Tags

New post 16 Sep 2017, 01:02
1
Option B-> Dispassionate

As author is indifferent towards Sea Otters.
Manager
Manager
User avatar
G
Joined: 05 Dec 2016
Posts: 105
Re: Of the many organisms found in marine ecosystems, sea otters play a un  [#permalink]

Show Tags

New post 07 May 2018, 06:42

VERITAS PREP OFFICIAL SOLUTION:


Correct Answer: A

The final sentence of the second paragraph states that: The extended consequences include local extinction of other species and vast urchin barrens: subtidal areas where the unchecked population growth of sea urchins has caused a dearth of kelp and, therefore, other marine species. This sentence sets the cause and effect relationship that the lack of kelp led to the lack of other marine species. Thus, it can be inferred that kelp provide a unique habitat for such species that were unable to survive in the absence of kelp.
_________________
lets all unite to reach our target together
CR Forum Moderator
avatar
V
Joined: 25 Apr 2018
Posts: 623
GMAT 1: 680 Q49 V34
Premium Member Reviews Badge CAT Tests
Re: Of the many organisms found in marine ecosystems, sea otters play a un  [#permalink]

Show Tags

New post 30 Aug 2018, 08:40
Quote:
1. The author's tone towards sea otters could best be described as

(A) disdainful
(B) dispassionate
(C) concerned
(D) critical
(E) jovial


Hi workout VeritasKarishma

Can you please help in answering question 1.
How the answer is B.
Overall the passage author doesn't seem to be dispassionate towards sea otters.\

Thanks!
_________________
Please give kudos if you found my posts helpful!

Project CR Butler - 2 CR's everyday
Senior RC Moderator
User avatar
V
Joined: 02 Nov 2016
Posts: 3478
GPA: 3.39
Re: Of the many organisms found in marine ecosystems, sea otters play a un  [#permalink]

Show Tags

New post 19 Jul 2019, 10:40
+1 Kudos to posts containing answer explanation of all questions
_________________
For new project RC Butler 2019: Click here
New! Need for an RC strategy and practice? Click here
Patterns among those who have scored 750+(2019 Edition) Click here
For all GMAT Flashcards => Click here
Intern
Intern
avatar
B
Joined: 25 Jul 2018
Posts: 3
Re: Of the many organisms found in marine ecosystems, sea otters play a un  [#permalink]

Show Tags

New post 19 Jul 2019, 13:31
How to find the answer to question 4?
Senior RC Moderator
User avatar
V
Joined: 02 Nov 2016
Posts: 3478
GPA: 3.39
Re: Of the many organisms found in marine ecosystems, sea otters play a un  [#permalink]

Show Tags

New post 21 Jul 2019, 23:26
In the 2nd paragraph read lines 20-22

Without sea otters, sea urchins and other seafloor herbivores would graze on kelp holdfasts, causing kelp to drift away from their substrates and die.

Options A, C, D and E did'nt supported by these lines only Option B is supported

Answer: B

Moubani wrote:
How to find the answer to question 4?

_________________
For new project RC Butler 2019: Click here
New! Need for an RC strategy and practice? Click here
Patterns among those who have scored 750+(2019 Edition) Click here
For all GMAT Flashcards => Click here
Director
Director
User avatar
P
Joined: 20 Sep 2016
Posts: 638
Location: India
Concentration: Strategy, Operations
GPA: 3.95
WE: Operations (Real Estate)
GMAT ToolKit User
Re: Of the many organisms found in marine ecosystems, sea otters play a un  [#permalink]

Show Tags

New post 22 Jul 2019, 00:31
Q1 gmat1393

Quote:
Of the many organisms found in marine ecosystems, sea otters play a uniquely significant role in maintaining their environments. Sea otters (Enhydra lutris) are a keystone species, a species whose effect on their environment is disproportionately great relative to their size in numbers or weight. Keystone species keep the growth of populations of other species in check and are thereby a determining factor of the type and number of other species in a community; keystone species are so named because their role is analogous to that of a keystone in an arch: while keystones bear the least amount of pressure among the components of an arch, the arch collapses without them.

-

in the first para author tells us that "otters = keystone species" ...author is neither + or - about this !!!

it is intimidating to think that author has a POV by the words " uniquely significant" ...but please note that the author is just describing the necessay object here.. by stating that " oxygen is necessary for humans" i am not taking a stand for oxygen... i am just being descriptive !!! here author is also being descriptive..
Quote:
The sea otter's reputation as a keystone species is largely a consequence of its affinity for sea urchins. Sea otters are known to prey upon over 100 different species, but the bulk of their diet consists of sea urchins and other marine invertebrates. Sea urchins are such highly preferred prey that sea otters have been known to significantly deplete urchin populations. In marine ecosystems at equilibrium, however, sea otters are often the primary force that keeps populations of sea urchins in check. Without sea otters, sea urchins and other seafloor herbivores would graze on help holdfasts, causing kelp to drift away from their substrates and die. The aggregate result of many such events leads to the destruction of entire kelp beds, resulting in a loss of habitat and nutrients for other organisms in the ecosystem. The extended consequences include local extinction of other species and vast urchin barrens: subtidal areas where the unchecked population growth of sea urchins has caused a dearth of kelp and, therefore, other marine species.


- here the author tells us : WHY SEA OTTERS ARE KEYSTONE
- no + or - POV by author

Quote:
This ecological cascade effect of secondary extinctions resulting from a decrease in otter populations and corresponding growth in urchin populations was observed throughout the 19th century along the Pacific coast of North America. Sea otters had been aggressively hunted for their rich pelts since before the 1600s, and this practice was not outlawed until an international treaty was signed in 1911 to prevent further exploitation. Prior to the enforcement of the treaty, hunters caused sea otter populations to decline; this in turn caused sea urchin populations to explode. Consequently, the urchin populations overexploited their primary food source, kelp, creating a preponderance of urchin barrens.


- function : how NO OTTER would indirectly affect something else...followed by examples
- again the author ony tells us what happened IN HISTORY when otter was depleted ... is he saying they should be saved NOW???
is he concerned that they are depleting?? NOOO
All the author is expanding on the fact that "OTTER IS A KEYSONE SPECIEIS " .....

1. The author's tone towards sea otters could best be described as

(A) disdainful - no negarivity - WRONG
(B) dispassionate - plainly explanding on a topic "otters are keysrone species " ...pure description.. NO STANDS
(C) concerned- plainly descriptive
(D) critical- WRONG
(E) jovial - NO POSITIVITY - WRONG
Manager
Manager
User avatar
B
Joined: 30 Oct 2018
Posts: 71
CAT Tests
Re: Of the many organisms found in marine ecosystems, sea otters play a un  [#permalink]

Show Tags

New post 31 Jul 2019, 14:44
m taking 10 mins for this paragraph.
how much time should I target for this big paragraph?
_________________

----------------------------------
Plz Kudos! if my post helps....
Senior Manager
Senior Manager
User avatar
G
Joined: 09 Aug 2017
Posts: 405
Re: Of the many organisms found in marine ecosystems, sea otters play a un  [#permalink]

Show Tags

New post 31 Jul 2019, 18:46
I am still not convinced with option B for question 1.
Sea otter, a keystone organism, maintains the ecology system indirectly. Though their the size and number might be less, sea otters play a key role to sustain the other organisms, keeping the urchins in check.
Prior to 1911, excessive hunting had caused depletion of sea otters, eventually leading to exploitation of other organisms by urchins.

With the above understanding, I think the author is concerned about sea otters.
C should be the correct choice.
GMAT Club Bot
Re: Of the many organisms found in marine ecosystems, sea otters play a un   [#permalink] 31 Jul 2019, 18:46
Display posts from previous: Sort by

Of the many organisms found in marine ecosystems, sea otters play a un

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  





Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne