Until recently, Ascaris azure, known as the Diaz blueworm, and Ascaris

Question

Until recently, Ascaris azure, known as the Diaz blueworm, and Ascaris tropica, known as the Costa Rican heatworm, were thought to be different species of roundworm. The heatworm is about 0.5 centimeters long, and lives within the bark of huge cecropia trees in Southeast Asian rain forests. The blueworm, barely visible with the naked eye, is found in frigid seafloors. Despite these apparent differences, the Institute of Helminthological Studies has officially stated that “both” species are actually Diaz blueworms.

Dr. Ginny Bolton, examining roundworm samples collected in Borneo, noticed that the heatworm’s tiny cilia (hairlike organelles) appeared to beat in a single direction, aiding in the expulsion of food. Dr. Bolton later determined that the cilia also made it much easier for the heatworm to live in the stifling confines of tree bark. The cilia project from a cuticle that is made of keratin, a protein that protects the worm’s epidermis from drying out and overheating. The cilia help regulate the proliferation of the keratin, and the force of the cilia’s movements varies as the external temperature changes, allowing for a highly responsive thermostatic system, constantly adjusting the amount of keratin so that the worm would be neither overexposed nor stifled.

Knowing that the only other roundworm with directional cilia is the blueworm, Dr. Bolton consulted with several blueworm specialists. The thermostatic system that served the heatworm so well proved to be identical to the one used by oceangoing blueworm. However, the blueworm, which has been known to colonize methane ice mounds, uses the keratin to protect itself from frigid temperatures. The cilia sensed when the temperature was high enough to allow the production of keratin to slow down. Without the surrounding wall of keratin, the worm can more easily graze on bacteria.

Genetic testing showed that the blueworm and the heatworm were not merely structurally similar; to the scientists’ surprise, the worms were identical. This was startling, not only because of their vastly differing habitats, but also because of the difference in size. The answer again was to be found in the keratin, a tough substance that normally inhibits growth, keeping the hydrostatic pressure very high within the worm. The relatively large worm found in the rainforest molts as it grows, allowing the worm to increase its volume a very small amount each time it does, but the smaller worm cannot afford this much exposure. The freezing temperatures trigger the production of keratin so quickly that the worm has little chance to grow, thus keeping its volume approximately one-fourth that of the larger worm.    1  
 1. It can be inferred from the passage that, compared to blueworms found in the sea, heatworms found in rainforests ___________.

(A) do not graze on bacteria
(B) do not have high levels of hydrostatic pressure
(C) cannot survive in water
(D) have little chance to grow because of extreme temperature
(E) replace keratin more slowly

2  
 2. It can be inferred from the passage that if the cilia of a blueworm found on the seafloor were to become damaged, preventing the sensing of warmer temperatures, the worm ______________.

(A) could grow to a length of 0.5 centimeters
(B) would be in danger of freezing
(C) might not be able to gain access to enough nourishment to sustain life
(D) would be forced to find its way to warmer temperatures
(E) would experience a sudden drop of hydrostatic pressure

3  
 3. According to the passage, researchers were able to make the discovery of the unlikely relationship between the two worms because of which of the following?

(A) Both worms have mechanisms to produce keratin.
(B) Both worms exist in extreme temperatures.
(C) Both worms are researched by the Institute of Helminthological Studies.
(D) Both worms feature directional cilia.
(E) Both worms molt as they grow.

4  
 4.Which of the following is the primary purpose of the passage? 
 
(A) To present an overview of the function of keratin in roundworms
(B) To give an example of the kind of discoveries that are still being made in the natural sciences
(C) To show the ways in which scientists who are highly specialized need to work together
(D) To provide some of the details of a surprising scientific discovery
(E) To show how genetic testing is an invaluable scientific tool

5  
 5. According to the passage, in what way do the blueworm’s cilia aid the worm in coping with extreme heat and cold? 
 
(A) They help with the removal of food from the worm’s system.
(B) They provide a mechanism by which the production of keratin can be regulated.
(C) They collect the bacteria on which some blueworms graze.
(D) They keep the hydrostatic pressure within the worm high.
(E) They keep it securely attached to the bark of the cecropia tree.

JarvisR · Answer

Good one. I crossed the time-limit on this one.

10 mins. 1. It can be inferred from the passage that, compared to blueworms found in the sea, heatworms found in rainforests ___________. (A) do not graze on bacteria (B) do not have high levels of hydrostatic pressure (C) cannot survive in water (D) have little chance to grow because of extreme temperature (E) replace keratin more slowly >> HW: The cilia project from a cuticle that is made of keratin, a protein that protects the worm’s epidermis from drying out and overheating. BW:The freezing temperatures trigger the production of keratin so quickly that the worm has little chance to grow, thus keeping its volume approximately one-fourth that of the larger worm. HW lives in hot climate, whereas BW in freezing climate. Using the info abt the relation between K production and temprature, we can infer E. 2. It can be inferred from the passage that if the cilia of a blueworm found on the seafloor were to become damaged, preventing the sensing of warmer temperatures, the worm ______________. (A) could grow to a length of 0.5 centimeters (B) would be in danger of freezing (C) might not be able to gain access to enough nourishment to sustain life >>The cilia sensed when the temperature was high enough to allow the production of keratin to slow down. Without the surrounding wall of keratin, the worm can more easily graze on bacteria. (D) would be forced to find its way to warmer temperatures (E) would experience a sudden drop of hydrostatic pressure 3. According to the passage, researchers were able to make the discovery of the unlikely relationship between the two worms because of which of the following? (A) Both worms have mechanisms to produce keratin. (B) Both worms exist in extreme temperatures. (C) Both worms are researched by the Institute of Helminthological Studies. (D) Both worms feature directional cilia. >>Knowing that the only other roundworm with directional cilia is the blueworm, Dr. Bolton consulted with several blueworm specialists. The thermostatic system that served the heatworm so well proved to be identical to the one used by oceangoing blueworm. (E) Both worms molt as they grow.

Nevernevergiveup · Answer

Worms have cilia and that regulates Keratin. Nowhere is a mechanism mentioned to produce keratin. So A is wrong. Mainly the answer to the question lies in highlighted portion of 3rd para ist line. I hope u understand my explanation :-D

goforgmat · Answer

I cannot understand the how OA for question 2 is C. Can you please explain or post the OE. 
My doubt here is when cilia is damaged keratin is not there which means it can easily graze on food using this extract for support -"Without the surrounding wall of keratin, the worm can more easily graze on bacteria". also second para states that cilia helps in expulsion of food. So if anything it should be the opposite of C.

Skywalker18 · Answer

Two questions added -

4.Which of the following is the primary purpose of the passage? 
(A) To present an overview of the function of keratin in roundworms
(B) To give an example of the kind of discoveries that are still being made in the natural sciences
(C) To show the ways in which scientists who are highly specialized need to work together
(D) To provide some of the details of a surprising scientific discovery
(E) To show how genetic testing is an invaluable scientific tool
 D

5. According to the passage, in what way do the blueworm’s cilia aid the worm in coping with extreme heat and cold? 
(A) They help with the removal of food from the worm’s system.
(B) They provide a mechanism by which the production of keratin can be regulated.
(C) They collect the bacteria on which some blueworms graze.
(D) They keep the hydrostatic pressure within the worm high.
(E) They keep it securely attached to the bark of the cecropia tree.

B

Skywalker18 · Answer

Veritas Prep OE -

Question #12 is quite similar to the earlier question about blueworms, and you should already know to head directly to paragraph three for that specific information. In that earlier question, we determined that the role of cilia was to sense warmer temperatures and control the production of keratin. Again, your job is to follow cause-and-effect relationships and, when the question asks you to “infer,” to recognize that you will likely have to leverage information. Here the next step is that “without the wall of keratin, the worm can more easily graze on bacteria.” This means that the cause/effect flowchart would read: cilia → sense temperature → slow production of keratin → allow worm to eat. This means that without the cilia, the effects that follow would also not occur. Therefore, answer choice C is correct: Without the properly functioning cilia, the worm might not be able to obtain enough nourishment.

gmatexam439 · Answer

I don't believe; I got all right. Though I took around 10 minutes for all 5 questions.
Below is my explanation for all the questions.

Until recently, Ascaris azure, known as the Diaz blueworm, and Ascaris tropica, known as the Costa Rican heatworm, were thought to be different species of roundworm. The heatworm is about 0.5 centimeters long, and lives within the bark of huge cecropia trees in Southeast Asian rain forests. The blueworm, barely visible with the naked eye, is found in frigid seafloors. Despite these apparent differences, the Institute of Helminthological Studies has officially stated that “both” species are actually Diaz blueworms.

Dr. Ginny Bolton, examining roundworm samples collected in Borneo, noticed that the heatworm’s tiny cilia (hairlike organelles) appeared to beat in a single direction, aiding in the expulsion of food. Dr. Bolton later determined that the cilia also made it much easier for the heatworm to live in the stifling confines of tree bark. The cilia project from a cuticle that is made of keratin, a protein that protects the worm’s epidermis from drying out and overheating. The cilia help regulate the proliferation of the keratin, and the force of the cilia’s movements varies as the external temperature changes, allowing for a highly responsive thermostatic system, constantly adjusting the amount of keratin so that the worm would be neither overexposed nor stifled.

Knowing that the only other roundworm with directional cilia is the blueworm, Dr. Bolton consulted with several blueworm specialists. The thermostatic system that served the heatworm so well proved to be identical to the one used by oceangoing blueworm. However, the blueworm, which has been known to colonize methane ice mounds, uses the keratin to protect itself from frigid temperatures. The cilia sensed when the temperature was high enough to allow the production of keratin to slow down. Without the surrounding wall of keratin, the worm can more easily graze on bacteria.

Genetic testing showed that the blueworm and the heatworm were not merely structurally similar; to the scientists’ surprise, the worms were identical. This was startling, not only because of their vastly differing habitats, but also because of the difference in size. The answer again was to be found in the keratin, a tough substance that normally inhibits growth, keeping the hydrostatic pressure very high within the worm. The relatively large worm found in the rainforest molts as it grows, allowing the worm to increase its volume a very small amount each time it does, but the smaller worm cannot afford this much exposure. The freezing temperatures trigger the production of keratin so quickly that the worm has little chance to grow, thus keeping its volume approximately one-fourth that of the larger worm.

1. It can be inferred from the passage that, compared to blueworms found in the sea, heatworms found in rainforests ___________.
(A) do not graze on bacteria - We don't know anything about the food of roundworm. 
(B) do not have high levels of hydrostatic pressure - The passage doesn't talk about hydro static pressure 
(C) cannot survive in water - We can't say this. We just know they are found in the barks of tree. Who knows if required, they could survive in ocean as well. 
(D) have little chance to grow because of extreme temperature - It is just the opposite of what is stated in the passage 
(E) replace keratin more slowly - Correct. " The freezing temperatures trigger the production of keratin so quickly that the worm has little chance to grow, thus keeping its volume approximately one-fourth that of the larger worm " --From here we can infer that keratin is replaced at a slower pace in roundworm than in blueworm.

E

2. It can be inferred from the passage that if the cilia of a blueworm found on the seafloor were to become damaged, preventing the sensing of warmer temperatures, the worm ______________.
(A) could grow to a length of 0.5 centimeters - We know that cilia helps in the regulation of keratin. If the temperatures are freezing the level of keratin will be higher. Now higher levels of keratin inhibit growth. As a result, this choice is opposite of what is stated in the passage. 
(B) would be in danger of freezing - If the worm can't sense warm water, cilia would keep the levels of keratin high, thus warm would never freeze 
(C) might not be able to gain access to enough nourishment to sustain life - Correct. " Without the surrounding wall of keratin, the worm can more easily graze on bacteria " -from here we can say that keratin barrier creates problem in the intake of food (bacteria). As a result as per the explanation given in option A above, if the levels of keratin are high, then the barrier will make it even more difficult for the worm to feed on anything. 
(D) would be forced to find its way to warmer temperatures - How? If the worm can't sense temperature changes, then how will it do so? 
(E) would experience a sudden drop of hydrostatic pressure - hydro static pressure is not mentioned in the passage

C

3. According to the passage, researchers were able to make the discovery of the unlikely relationship between the two worms because of which of the following?
(A) Both worms have mechanisms to produce keratin. - Incorrect 
(B) Both worms exist in extreme temperatures. - Incorrect 
(C) Both worms are researched by the Institute of Helminthological Studies. - Incorrect 
(D) Both worms feature directional cilia. - Correct. " Knowing that the only other roundworm with directional cilia is the blueworm, Dr. Bolton consulted with several blueworm specialists " 
(E) Both worms molt as they grow. - Incorrect

D

4.Which of the following is the primary purpose of the passage? 
(A) To present an overview of the function of keratin in roundworms - The passage is concerned about the discovery 
(B) To give an example of the kind of discoveries that are still being made in the natural sciences - still being made? 
(C) To show the ways in which scientists who are highly specialized need to work together - wrong 
(D) To provide some of the details of a surprising scientific discovery - Correct 
(E) To show how genetic testing is an invaluable scientific tool - wrong

D

5. According to the passage, in what way do the blueworm’s cilia aid the worm in coping with extreme heat and cold? 
(A) They help with the removal of food from the worm’s system. - Not stated in the passage 
(B) They provide a mechanism by which the production of keratin can be regulated. - Correct. " the blueworm, which has been known to colonize methane ice mounds, uses the keratin to protect itself from frigid temperatures. The cilia sensed when the temperature was high enough to allow the production of keratin to slow down " 
(C) They collect the bacteria on which some blueworms graze. - some? wrong 
(D) They keep the hydrostatic pressure within the worm high. - hydro static pressure is not mentioned in the passage 
(E) They keep it securely attached to the bark of the cecropia tree. - wrong. blueworm are found in ocean

B

shrgmat · Answer

I am not sure I agree with eliminating B. Hydrostatic pressure is unique to BW. It seems to me that this specific Qn has 2 answers.

akankshasehgal16 · Answer

Even I felt that, high levels of keratin = high hydrostatic pressure, and since seafloor worms are known to have higher levels of keratin than than levels in heatworms, it implies that heatworms should have at least lower levels of hydrostatic pressure.

Experts, please clarify  VeritasKarishma   egmat   GMATNinja

KarishmaB · Answer

1. It can be inferred from the passage that, compared to blueworms found in the sea, heatworms found in rainforests ___________.

The question is looking for a point of difference between blue worm and heat worm.

(B) do not have high levels of hydrostatic pressure

Heat worms produce keratin too, albeit at a slower pace and they molt when they grow so they grow to larger sizes. Since blue worms cannot afford this much exposure, they keep producing keratin at a fast pace. 
Since heat worms produce keratin too, the hydrostatic pressure inside them is likely to be high too ( ... keratin, a tough substance that normally inhibits growth, keeping the hydrostatic pressure very high within the worm... )
Yes, the hydrostatic pressure inside the blue worm might be higher but heat worm is likely to have high hydrostatic pressure too due to the presence of keratin. This option does not say that heat worms have lower hydrostatic pressure compared to blue worms. It only says that the difference is that heat worms do not have high hydrostatic pressure. This is not correct.

(E) replace keratin more slowly
This is a point of distinction. It says heat worms replace keratin more slowly than blue worms. This we know is correct.

RiyaJ0032 · Answer

can somebody help with Q3

why isn't the answer A?

doesn't it correspond to the surprising finding which led researchers to conclude that both worms are structurally similar

while (D) is given in the RC, but weren't the researchers aware from before , about the directional cilia part?
When the two worms were classified into separate categories, researchers knew right, that both have cilia?

but it was the surprising finding which led researchers to treat both worms in one category

can someone explain

KarishmaB 
 GMATNinja

Until recently, Ascaris azure, known as the Diaz blueworm, and Ascaris

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Until recently, Ascaris azure, known as the Diaz blueworm, and Ascaris

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