Verbal Practice Exercise-11

Reading Comprehension:

Other Specific Question Exercise:

Anole lizard species that occur together (sympatrically) on certain Caribbean islands occupy different habitats: some live only in the grass, some only on tree trunks, and some only on twigs. These species also differ morphologically: grass dwellers are slender with long tails, tree dwellers are stocky with long legs, twig dwellers are slender but stubby-legged. What is striking about these lizards is not that coexisting species differ in morphology and habitat use (such differences are common among dosely related sympatric species), but that the same three types of habitat specialists occur on each of four islands: Puerto Rico, Cuba, Hispaniola, and Jamaica. Moreover, the Puerto Rican twig species closely resembles the twig species of Cuba, Hispaniola, and Jamaica in morphology, habitat use, and behavior. Likewise, the specialists for other habitats are similar across the islands.

The presence of similar species on different islands could be variously explained. An ancestral species might have adapted to exploit a particular ecological niche on one island and then traveled over water to colonize other islands. Or this ancestral species might have evolved at a time when the islands were connected, which some of these islands may once have been. After the islands separated, the isolated lizard populations would have become distinct species while also retaining their ancestors’ niche adaptations. Both of these scenarios imply that specialization to each niche occurred only once. Alternatively, each specialist could have arisen independently on each of the islands.

If each type of specialist evolved just once, then similar specialists on different islands would be closely related. Conversely, if the specialists evolved independently on each island, then a specialist on one island would be more closely related to other types of anoles on the same island—regardless of their ecological niches—than it would be to a similar specialist on a different island.

Biologists can infer how species are related evolutionarily by comparing DNA sequences for the same genes in different species. Species with similar DNA sequences for these genes are generally more closely related to each other than to species with less-similar DNA sequences. DNA evidence concerning the anoles led researchers to conclude that habitat specialists on one island are not closely related to the same habitat specialists elsewhere, indicating that specialists evolved independently on each island.

1. According to the passage, sympatric anole lizard species resemble many other closely related sympatric species in that the anole lizard species

A. differ from one another in morphology and habitat use
B. evolved on islands that were once connected
C. appear to have adapted unusually quickly to new habitats
D. have been able to colonize areas remote from their ancestral habitat
E. occupy the same range of habitats in a number of different locations

2. According to the passage, all the habitat specialists of Anole Lizards found on the four islands of Puerto Rico, Cuba, Hispaniola, and Jamaica

A. differ in morphology and habitat use that is typical of differences among closely related sympatric species.
B. evolved on one of the islands and then migrated to the other islands.
C. demonstrate a higher degree of genetic similarity amongst themselves than with the Anole lizards on their respective islands.
D. evolved on each of the islands independently.
E. share a common morphology characterized by stubby legs and long tails.

Despite the prevalence of brain injury from kindergarten to high school, relatively little research on the long-term health consequences of concussion has been conducted on child athletes, compared with the research on athletes in college and in the pros. The problem is severe. According to the Journal of Pediatrics, about 144,000 people aged 18 and younger are treated every year in U.S. hospital emergency rooms for concussions, nearly one third caused by participation in organized sports. Overall, concussions are most common in football and ice hockey, followed by soccer, wrestling, and other sports and slightly more boys than girls suffer concussions. As participation in sports continues to grow, more head injuries are inevitable, making pediatric concussions an emerging public health crisis.

Doctors and public health experts are concerned about the effect of repeat concussions that occur before the brain has had a chance to heal from a prior impact. The current data on adults indicated that effects of repeat concussions can be quite serious. A study commissioned by the NFL found that retired players were 19 times more likely than other men of similar ages to develop severe memory problems including Parkinson’s disease or perhaps even amyotrophic lateral sclerosis. The obvious culprit: continued play after repeated head injuries.

Most people assume, for instance, that loss of consciousness is the defining feature of all concussions. Yet “seeing stars,” headache, nausea, dizziness, confusion, irritability, and an inability to remember events before or after the injury are the most common symptoms. However, because people don’t recognize these warning signs, youngsters may continue to play when they should not. Similarly, because the most obvious symptoms usually disappear within a few minutes to hours, children often return to normal activities too quickly, thereby overtaxing their injured brain. Even the added neural exertion from mental activities such as reading and video games can interfere with the cerebrum’s ability to heal—particularly in the first 24 hours after injury. The increased use of protective headgear also seems to have increased the risk of concussion by providing a false sense of security that encourages athletes to hit harder with their head.

Some states such as Minnesota passed a law which requires coaches to undergo training to recognize concussions and mandates the immediate removal of any player from a game at the first sign of dizziness or confusion. However, the law could have the unintended effect of giving kids an incentive to hide their symptoms. The way around that problem, of course, is for schools, sports leagues, and other organizations to join public health experts in raising ever greater awareness among coaches, parents, and children to play it smart and take brain injury very seriously.

3. According to the passage the ill effects of concussion are

A. not as prevalent in adults who play football as they are in kids.
B. more severe in adults who play football than kids.
C. more grave in adults who start playing football as kids and continue to play it as they reach their twenties.
D. much better researched in adults than in kids.
E. progress in kids much faster than they do in adults.

4. Which of the following is not a symptom of concussion as discussed in the passage?

A. Headache
B. Stomachache
C. Seeing starts in day
D. nausea
E. fainting

Answer Sheet:

1. A
2. D
3. D
4. B