That axon malfunction plays a role in neurological disorders has never been in question by neurobiologists, but the nature of the relationship has been a matter of speculation. Enter George Bartzokis. Bartzokis`s neurological research at UCLA suggests that many previously little understood disorders such as Alzheimer`s disease may be explained by examining the role of the chemical compound myelin.
Myelin is produced by oligodendrocyte cells as a protective sheathing for axons within the nervous system. As humans mature and their neurochemistries grow more complex, oligodendrocyte cells produce increasing amounts of myelin to protect thebyzantinecircuitry inside our nervous systems. An apt comparison may be to the plastic insulation around copper wires. Bereft of myelin, certain areas of the brain may be left vulnerable to short circuiting, resulting in such disorders as ADHD, schizophrenia, or autism.
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Consider each of the choices separately and select all that apply.
It can be inferred from the passage that the author would be most likely to agree with which of the following statements regarding the role of myelin?
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The nineteenth century marked a revolutionary change in the way that wealth was perceived in England. As landed wealth gave way to monied wealth, investments became increasingly speculative.
A popular investment vehicle was the three-percent consol which took its name from the fact that it paid three pounds on a hundred pound investment. The drawback to the consol was that once issued, there was no easy way for the government to buy back the debt. To address the problem, the British government instituted a sinking fund, using tax revenue to buy back the bonds in the open market. The fact that the consol had no fixed maturity date ensured that any change in interest rate was fully reflected in the capital value of the bond. The often wild fluctuation of interest rates ensured the consol`s popularity with speculative traders.
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Which of the following best describes the relationship of the first paragraph of the passage to the passage as a whole?
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Often the most influential developments initially appear to be of minor significance. Take stirrups. Without them, horse and rider are, in terms of force, separate entities; lances can be used from horseback, but only by throwing or stabbing, and mounted warriors gain only height and mobility. A lance couched under the rider`s arm, unifying the force of rider and weapon, would throw its wielder backwards off the horse at impact. Stirrups unify lance, rider, and horse into a force capable of unprecedented violence. This development left unusually clear archaeological markers: Lethality assured, lances evolved barbs meant to slow progress after impact, lest the weight of body pull rider from horse. The change presaged the dominance of mounted combat, and increasingly expensive equipment destroyed the venerable ideal of freeman warriors. New technology demanded military aristocracy, and chivalric culture bore its marks for a millennium.
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The primary purpose of the passage is to
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Few mathematical constructs seem as conceptually simple as that of randomness. According to the traditional definition, a number is random if it is chosen purely as the result of a probabilistic mechanism such as the roll of a fair die. In their groundbreaking work regarding complexity and the limitations of formal systems, mathematicians Gregory Chaitin and A.N. Kolmogorov force us to consider this last claim more closely.
Consider two possible outcomes of throwing a fair die three times: first, 1, 6, and 2; second 3, 3, and 3. Now let us construct two three-member sets based on the results. Though the first set-{1,6,2}-intuitively seems more random than the second-{3,3,3}, they are each as likely to occur, and thus according to the accepted definition, must be considered equally random. This unwelcome result prompts Chaitin and Kolmogorov to suggest the need for a new standard of randomness, one that relies on the internal coherence of the set as opposed to its origin.
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Which of the following best describes the organization of the passage as whole?
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For how many of the years shown did the ratings for Program y increase over the ratings for Program y the previous year?
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Despite the smile that spread from ear to ear, her eyes relayed a certain _____.
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Some historians see the Jacksonians as little more than ruthless capitalists who had _____ regard for individual welfare.
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One of social science`s major themes is that of stability versus change; to what extent are individual personalities _____ yet different over time?
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The Erie Canal`s completion caused _____ economic ripples; property values and industrial output along its route rose exponentially.
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Voters have become so inured to the fickle nature of politicians that they responded to the levy of a new tax with _____.
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The division between child-rearing goals that emphasize originality and personalization and those that place emphasis on adoption of conventions and compliance with rules discloses a _____that stems from the principles on which these goals are based.
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Possessed of an insatiable sweet tooth, Jim enjoyed all kinds of candy, but he had a special_____for gumdrops, his absolute favorite.
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Although the Wright brothers first attempted flight in 1896 was a_____and subsequent efforts similarly ended in failure, they persisted and ultimately made the first successful airplane flight in 1903.
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The fuel efficiency of most vehicles traveling speeds greater than 40 miles per hour_____as the vehicle`s speed increases, due to the additional demands placed on the vehicle.
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Robert`s outwardly amiable disposition belied his_____nature; he was more than willing to badmouth a colleague`s work or spread gossip if he thought it would help him advance his career.
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