GRE GRE Certifications GRE-TEST Questions & Answers

• Question 201:

  Like paleontologists who interpret timescales from fossil evidence, we infer the history of star formation in the Milks' Way galaxy from the heavy-element composition of its stars. According to the big bang theory of the origin of the universe, the first gas clouds--and the first generation of stars formed from them--were composed of pure hydrogen and helium; most heavier elements-- iron and calcium, for example--came later, created by explosions of supernovas, massive stars in their death thaws. Loaded with heavy elements, material ejected from supernovas enriched the interstellar gas clouds from which the next generation of stars formed, the level of heavy elements increasing with succeeding generations. Because most stars live for many billions of years and because the Milky Way is thus composed of multiple stellar generations, comparing the number of stars of low heavy-element abundance with those of high heavy-element abundance enables astronomers to untangle the history of star formation in the Milky Way.

  The passage implies that if a star contains calcium, then the

  A. star does not belong to the first generation of stars

  B. star does not contain any hydrogen or helium

  C. calcium was not formed by the explosion of a supernova

  Correct Answer: A

• Question 202:

  She constantly_________herself for not living up to her own ideals--for not working hard enough, or not having motives that were pure enough.

  A. exalted

  B. coddled

  C. excoriated

  D. mollified

  E. deluded

  Correct Answer: C

• Question 203:

  Many environmentalists who revere nature would find the intellectual traditions of Rousseau. Kropotkin. and Jefterson much more compatible with their vision than that of Marx, who_________the domination of nature by humans.

  A. abhorred

  B. underestimated

  C. revealed

  D. distrusted

  E. commended

  Correct Answer: E

• Question 204:

  Sunflower sea stars help maintain certain kelp forest ecosystems by eating quickly reproducing prey species such as urchins, thus keeping populations low. Without the sea stars, the urchin population explodes, which is bad news for kelp forests and everything in them. Gianl kelp can grow to 150 feet underwater at a speed of two feet a day. but their weaknesses are their holdfasts. which are akin to tree roots. The holdfasts are home to brittle stars, prawns, and snails, among other creatures. Urchins like to eat the kelp holdfasts. Once the holdfasts are gone, the rest of the kelp drifts oft* in the tides. In this way. urchins can destroy the forests, which, higher up. are also home (o fish, including several types of commercially important rockfish,

  The passage compares kelp holdfasts to tree roots in order to

  A. indicate the role of holdfasts in the acquisition of nutrients

  B. emphasize the structural function of holdfasts

  C. rationalize the use of the term "kelp forest"

  D. point out similarities between terrestrial and aquatic flora

  E. identify a misconception about kelp anatomy

  Correct Answer: B

• Question 205:

  Recent research has questioned the long-standing view of pearly mussels as exclusively suspension feeders (animals that strain suspended particles from water) that subsist on phytoplankton (mostly algae). Early studies of mussel feeding were based on analyses of gut contents, a method that has three weaknesses. First, material in mucus-bound gut contents is difficult to identify and quantify. Second, material found in the gut may pass undigested out of the mussel, not contributing to its nutrition. Finally, examination of gut contents offers limited insight into the mechanisms and behaviors by which mussels acquire food. Modem studies suggest that pearly mussels feed on more than just algae and may use other means than suspension feeding. Pedal feeding (sweeping up edible material with a muscular structure called the foot) has been observed in juvenile pearly mussels.

  Besides the phytoplankton pearly mussels capture from the water column, their guts also contain small animals, protozoans, and detritus (nonliving particulate organic material). Recent studies show that mussels can capture and assimilate bacteria as well, a potentially important source of food in many fresh waters. Another potential source of food for mussels is dissolved organic matter. Early studies showing that pearly mussels could take up simple organic compounds were largely discounted because such labile (unstable) compounds are rarely abundant in nature. Nevertheless, recent work on other bivalves suggests that dissolved organic matter may be a significant source of nutrition.

  Of this complex mix of materials that pearly mussels acquire, what is actually required and assimilated? Stable-isotope analyses of mussels taken from nature and of captive-reared mussels are beginning to offer some insight into this question. Nichols and Garling showed that pearly mussels in a small river were omnivorous, subsisting mainly on particles less than 2S micrometers in diameter, including algae, detritus, and bacteria. Bacterially derived carbon was apparently the primary source of soft-tissue carbon. However, bacteria alone cannot support mussel growth, because they lack the necessary long-chain fatty acids and sterols and are deficient in some amino acids. Bacteria may supplement other food resources, provide growth factors, or be the primary food In habitats such as headwater streams, where phytoplankton is scarce. Juvenile mussels have been most successfully reared m the laboratory on diets containing algae high in polyunsaturated fatty acids. Thus, it appears that the pearly mussel diet in nature may consist of algae, bacteria, detritus, and small animals and that at least some algae and bacteria may be required as a source of essential biochemicals.

  Which of the following can be inferred from the passage about the research findings of Nichols and Garling?

  A. They are based on analyses of gut contents of pearly mussels.

  B. They suggest that pearly mussels are unable to assimilate bacteria.

  C. They demonstrate the importance to pearly mussels of long-chain fatty acids.

  D. They contradict the long-standing view mentioned at the beginning of the passage.

  E. They shed light on a puzzling phenomenon detailed in the second paragraph.

  Correct Answer: D

• Question 206:

  As originally formulated, the selfish-herd theory of prey species aggregation assumed that predatory attacks were equally likely to be launched from any position within the environment. In some circumstances (e.g.. avian predators attacking prey from above), such an approach is appropriate. However, as James et al. argue, in many predator-prey associations, attacks are unlikely to occur from positions within the group. For example, it is likely that an ambushing predator waiting in the path of a group would be detected before the group moves over its position. Hence, in many ecological situations, predatory attacks on grouped prey will occur exclusively from outside the group. In such circumstances, there is a strong premium to a group member in being in the interior of the group. James would most likely describe the original formulation of the selfish-herd theory as

  A. completely untenable in its explanation of predator-prey associations

  B. ill-equipped to explain exceptions to standard predator-prey associations

  C. insufficiently attentive to the diversity of predator-prey associations

  D. excessively concerned with the outcomes of predator-prey associations

  E. problematically neglectful of the cooperative elements of predator-prey associations

  Correct Answer: C

• Question 207:

  Since it was committed to the idea of science as an international, politically neutral enterprise, the Royal Society of London refused to_________members from enemy nations during the world wars of the twentieth century.

  A. betray

  B. expel

  C. endorse

  D. oust

  E. sanction

  F. condemn

  Correct Answer: BD

• Question 208:

  Even if the merits of the proposal are (i)_________, faculty members may be reluctant to (ii)_________given their fear of offending the group that champions it.

  A. unparalleled

  B. dubious

  C. obvious

  D. approve

  E. acquiesce

  Correct Answer: BD

• Question 209:

  The sound of disembodied human breathing in Miyazakrs films is at once a presence, close to the listener s ear. and a ghostly absence due to its lack of a visual_________.

  A. image

  B. counterpart

  C. urgency

  D. correlative

  E. cue

  F. background

  Correct Answer: BD

• Question 210:

  Though mathematics is________, like language, it has its roots in the mud of everyday embodied

  experience: one such root is counting.

  A. essential

  B. indispensable

  C. abstract

  D. theoretical

  E. prescriptive

  F. functional

  Correct Answer: CD