Fixed Sir

Thank you

Can someone explain why the answer of 19 is not (C)? For me "This suggests that bacterial chemosynthesis is not a sufficient source of nutrition for these creatures." and "chemosynthesis can account for only a fraction of the vent faunas." means that the bacteria cannot produce food fast enough. Where am I going wrong?

Thanks in advance!

and extremely large concentrations of bacteria were found in samples of vent water thought to be pure. This final observation seemed decisive. If such astonishing concentrations of bacteria were typical of vent outflow, then food within the vent would dwarf any contribution from advection. Hence, the widely quoted conclusion was reached that bacterial chemosynthesis provides the foundation ,for hydrothermal-vent food chains - an exciting prospect because no other communities on Earth are independent of photosynthesis.

If we find that the community is NOT independent and that the bacteria is NOT the only key element of the colony we can weaken the argument

A says just this

(A) Vents are colonized by some of the same animals found in other areas of the ocean floor.

C is wrong

(C) Bacteria cannot produce large quantities of food quickly enough.

because to weaken our argument is not the production of food rather their presence as unique. The ONLY key element for the chemosynthesis


Hope this helps

Q22: I thought that since 300mg can lead to 30KG doesn't that mean the "large "particulate matter? As in food is getting transported via large congregation

22 is a bit tricky.

In the 2nd paragraph is explained some alternative solution that generates food. However in the third they back on the first possible explanation for food which is advection

Nonetheless, advection is a more likely alternative food source. Research has demonstrated that advective flow, which originates near the surface of the ocean where suspended particulate matter accumulates, transports some of that matter and water to the vents. Estimates suggest that for every cubic meter of vent discharge, 350 milligrams of particulate organic material would be advected into the vent area.

This is the key phrase

Thus, for an average-sized vent, advection could provide more than 30 kilograms of potential food per day. In addition, it is likely that small live animals in the advected water might be killed or stunned by thermal and/or chemical shock thereby contributing to the food supply of vents.


22. Which of the following can be inferred from the passage about the particulate matter that is carried down from the surface of the ocean?

(A) It is the basis of bacterial chemosynthesis in the vents.

We care about transportation not the key nutrition elements

(B) It may provide an important source of nutrition for vent faunas.

Correct. Kg of food per day

(C) It may cause the internal temperature of the vents to change significantly.

The temperature is discussed in the second one.

(D) It is transported as large aggregates of particles.

never mentioned large aggregates

(E) It contains hydrogen sulfide

I did not hydrogen

I failed in question 17. I marked A but the correct answer is B. and is B due to the first paragraph:



The first passage is clear about the size of animals in the deep sea, the are tiny except near hydrothermal vents.

EXTREMELY BAD WAY OF SHARING ANSWERS

I agree but not be too tough Sir

Please.

Regards

Kinda late sorry, but the question asks what the Author CITES.... author never cites that bacteria cannot produce food fast enough (that was your own deduction).

However, Author does cite this : "For example, some of the large sedentary organisms associated with vents are also found at ordinary deep-sea temperatures many meters from the nearest hydrothermal sources." which is answer choice A.

I was confused by the word nonvent as I thought it was just another vocab that I don't know. Shouldn't it be non-vent?

6/6 in an untimed manner (18 mins 30 seconds )

Too much even though the actual passage are composed by 4 questions at most

Read my Time management guide https://gre.myprepclub.com/forum/gre-time- ... 19697.html

Regards

Vent means expressing emotions or creative energy. is it okay??

Is there any easy technic for answering question 16 ??
because how can I detect the answer asap??

Hi

question 16 has to deal with the main idea of the passage. Now, I strongly suggest you read my two examples of what I call "Black-Hole Strategy" or dealing with a question, tough, WITHOUT reading the passage. you can find here to examples

https://gre.myprepclub.com/forum/is-the-li ... tml#p45986

https://gre.myprepclub.com/forum/some-rece ... tml#p58341

Back to your question.

When you need to find the overall idea that the passage conveys you must read in brief the key elements of the passage itself. Actually, there is not a bullet-proof strategy because the answer arose from the sense and feeling you do have from it. Of course, there is a logic in answering it. However, these kinds of questions are NOT based on pure logic but rather common sense

Answer this question in 30 seconds is possible

Look at these key parts



two crucial elements here: however which is a shift in the argument and put you in the path that the passage talks about something else of that which is apparent and areas, which implies locations










16. The passage provides information for answering which of the following questions?

(A) What causes warm-water vents to form?

In the above quotation NO sign of warm water is the key element but rather the vent

(B) Do vent faunas consume more than do deep-sea faunas of similar size?

the consumption is NOT the key element

(C) Do bacteria live in the vent water of smokers?

The key element is the vent which is basically a location, an area for food and blah blah blah.....CORRECT

(D) What role does hydrogen sulfide play in chemosynthesis?

Hydrogen is NOT a key element of what we are talking about. Notice how this is tricky because the passage talks about hydrothermal vents NOT hydrogen

(E) What accounts for the locations of deep-sea smokers?

The passage talks about the proximity of deep-sea animals to smokers areas which are still VENT areas.

From all above as you can see if you are able to use this strategy even the most complex passages can be addressed in 30 seconds. However, this implies that your level of standard English is pretty decent

regards

vent is an outlet, a crack or an open hole

Think about the mouth of a Volcano, actually, that is a vent from which the lave comes out

Regards

16. The passage provides information for answering which of the following questions?

relevant lines from the passage

Another difficulty is that similarly dense populations of large deep-sea animals have been found in the proximity of "smokers" - vents where water emerges at temperatures up to 350° C. No bacteria can survive such heat, and no bacteria were found there Unless smokers are consistently located near more hospitable warm-water vents, chemosynthesis can account for only a fraction of the vent faunas.

(A) What causes warm-water vents to form?. Wrong
(B) Do vent faunas consume more than do deep-sea faunas of similar size?. Wrong
(C) Do bacteria live in the vent water of smokers?. Correct
(D) What role does hydrogen sulfide play in chemosynthesis?. Wrong
(E) What accounts for the locations of deep-sea smokers?. Wrong



17. The information in the passage suggests that the majority of deep-sea faunas that live in nonvent habitats have which of the following characteristics?

If you missed the first paragraph, you can still use the process of elimination to arrive at the correct answer. Nothing in the passage supports Choices A, C, D and E, so B must be the correct answer.

relevant lines in the passage

The deep sea typically has a sparse fauna dominated by tiny worms and crustaceans, with an even sparser distribution of larger animals. However, near hydrothermal vents, areas of the ocean where warm water emerges from subterranean sources, live remarkable densities of huge clams, blind crabs, and fish.

(A) They do not normally feed on particles of food in the water. Wrong
(B) They are smaller than many vent faunas. Correct
(C) They are predators. Wrong
(D) They derive nutrition from a chemosynthetic food source. Wrong
(E) They congregate around a single main food source. Wrong


18. The primary purpose of the passage is to

Explanation

A study of the passage reveals that it is trying to explain the food source for the dense populations for small and large animals near hydrothermal vents. Initially, the conclusion was reached that bacterial chemosynthesis provides the foundation for hydrothermal - vent food chains - on the basis of some evidence. Later evidence pointed towards advection as a more likely food source.

(A) describe a previously unknown natural phenomenon. Wrong.
(B) reconstruct the evolution of a natural phenomenon. Wrong.
(C) establish unequivocally the accuracy of a hypothesis. Wrong.
(D) survey explanations for a natural phenomenon and determine which is best supported by evidence. Correct.
(E) entertain criticism of the author's research and provide an effective response. Wrong.


19. Which of the following does the author cite as a weakness in the argument that bacterial chemosynthesis provides the foundation for the food chains at deep-sea vents?

relevant lines from the passage

For example, some of the large sedentary organisms associated with vents are also found at ordinary deep-sea temperatures many meters from the nearest hydrothermal sources. This suggests that bacterial chemosynthesis is not a sufficient source of nutrition for these creatures. Another difficulty is that similarly dense populations of large deep-sea animals have been found in the proximity of "smokers" - vents where water emerges at temperatures up to 350° C. No bacteria can survive such heat, and no bacteria were found there


(A) Vents are colonized by some of the same animals found in other areas of the ocean floor. Correct.
(B) Vent water does not contain sufficient quantities of hydrogen sulfide. Wrong.
(C) Bacteria cannot produce large quantities of food quickly enough. Wrong.
(D) Large concentrations of minerals are found in vent water.Wrong.
(E) Some bacteria found in the vents are incapable of chemosynthesis. Wrong.


20. Which of the following is information supplied in the passage that would support the statement that the food supplies necessary to sustain vent communities must be many times that of ordinary fallout?

relevant lines from the passage

The deep sea typically has a sparse fauna dominated by tiny worms and crustaceans, with an even sparser distribution of larger animals. However, near hydrothermal vents, areas of the ocean where warm water emerges from subterranean sources, live remarkable densities of huge clams, blind crabs, and fish.

I. Large vent faunas move from vent to vent in search of food. Wrong.
II. Vent faunas are not able to consume food produced by photosynthesis. Wrong.
III. Vents are more densely populated than are other deep-sea areas. Correct.

(A) I only Wrong.
(B) III only Correct.
(C) I and II only Wrong.
(D) II and III only Wrong.
(E) I, II, and III Wrong.


21. The author refers to "smokers" most probably in order to

relevant lines from the passage

Another difficulty is that similarly dense populations of large deep-sea animals have been found in the proximity of "smokers" - vents where water emerges at temperatures up to 350° C. No bacteria can survive such heat, and no bacteria were found there. Unless smokers are consistently located near more hospitable warm-water vents, chemosynthesis can account for only a fraction of the vent faunas.

(A) show how thermal shock can provide food for some vent faunas by stunning small animals. Wrong.
(B) prove that the habitat of most deep-sea animals is limited to warm-water vents. Wrong.
(C) explain how bacteria carry out chemosynthesis. Wrong.
(D) demonstrate how advection compensates for the lack of food sources on the seafloor. Wrong.
(E) present evidence that bacterial chemosynthesis may be an inadequate source of food for some vent faunas. Correct.


22. Which of the following can be inferred from the passage about the particulate matter that is carried down from the surface of the ocean?

relevant lines from the passage

Research has demonstrated that advective flow, which originates near the surface of the ocean where suspended particulate matter accumulates, transports some of that matter and water to the vents. Estimates suggest that for every cubic meter of vent discharge, 350 milligrams of particulate organic material would be advected into the vent area. Thus, for an average-sized vent, advection could provide more than 30 kilograms of potential food per day.In addition, it is likely that small live animals in the advected water might be killed or stunned by thermal and/or chemical shock thereby contributing to the food supply of vents.

(A) It is the basis of bacterial chemosynthesis in the vents. Wrong.
(B) It may provide an important source of nutrition for vent faunas. Correct
(C) It may cause the internal temperature of the vents to change significantly.. Wrong.
(D) It is transported as large aggregates of particles. Wrong.
(E) It contains hydrogen sulfide. Wrong.