题目内容
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Bluegills, which are small enough to fit in your hand, are the fish that are protecting our water. They are common freshwater fish native to America and are also known as bream or sunfish. According to the Associated Press, the bluegills were originally used by the Army to make sure water was safe. Now San Francisco, New York City, Washington D.C and several other cities use the bluegill monitoring system.
The bluegill system works by constantly filling the fish tank with city or town water. A small group of bluegills swim in the local water and are closely monitored. Bluegills are very sensitive to their environment. Changes in the environment cause their behavior and breathing patterns to change. They cough if the water is polluted. Fish cough by flexing their gills（鳃）to get rid of unwanted particles, like grain of sand, from their breathing passages. If the bluegills are coughing the computer sends an alarm via email. The bluegills in New York City discovered an diesel spill（柴油外溢）hours before the usual monitors. Adding the bluegill system to regular water protection methods resulted in an early warning and safer water.
People use the bluegill system to monitor water supplies_____.
A. because they have high sensibility to their environment
B. because they are used to swimming in the fresh water
C. because they can cough by means of their gills
D. because they are able to send e-mails by computers
Which of the following statements about Bluegills is NOT true?
A. They are about the size of a human hand.
B. They are freshwater fish easily found in America.
C. They were used to safeguard water in the army.
D. They are smarter than any other living thing on earth.
People decide whether the water is polluted by means of _____.
A. information sent by the Army
B. the warning e-mail the computer sends
C. observing the activities of bluegills
D. constantly filling the fish tank with water
ADB
There are some things humans can go without. We can lose a kidney or a lung, an arm or two and still live perfectly well. But some fish put us to shame. They can get by without stomachs.
One such fish is the stout longtom. The group it belongs to carries a more appropriate name: the needlefish. All needlefish lack stomachs. Their ancestors had them, but later they were lost.
The stout longtom can reach 1.3 meters in length, and lives near the sea surface. Like all needlefish, it can jump out of the water to escape its enemies. Tropical fishermen are sometimes injured by needlefish. In 1977, a 10-year-old Hawaiian boy was killed when a needlefish jumped through his brain. The longtom eats smaller fish. It teeth are not good at cutting fish into pieces, so it swallows fish whole.
Ryan Day from Australia and his colleagues wanted to know how the longtom digests its meaty meals without a stomach, so they ran some chemical tests about the fish.
Day’s results show that the longtom can consume food without the help of a stomach. It uses a special material called trypsin that can break down proteins without acid — although the approach is less efficient than using a stomach.
Because it’s a meat-eating animal, the longtom gets a lot of protein in its food, so it can afford this slightly less efficient system for absorbing it. Two plant-eating fish that Day studies actually had higher levels of trypsin in their body, as their food was low in protein.
Day thinks that the longtom and its stomachless relatives might actually have arrived at an energy-saving solution. He says that although the stomach is critical to many kinds of animal, the organ is “a fairly expensive organ to run”. This perhaps explains why some animals have got rid of theirs.
【小题1】What does the underlined phrase “get by” mean?
| A．Recover. | B．Fight. | C．Hunt. | D．Live. |
| A．catches smaller fish in the water | B．digests the smaller fish in its body |
| C．can jump so high to escape its enemies | D．uses acid to break down the protein |
| A．Trypsin. | B．Acid | C．The stomach. | D．Protein in its body. |
| A．the longtom can make acid easily |
| B．the longtom often waste energy |
| C．the longtom’s high-protein food helps its unique way of consuming food. |
| D．meat –eating fish have higher levels of trypsin in their bodies than plant-eating fish |
Scientists in Canada say big ocean fish have almost disappeared from the world since the start of industrial fishing in the nineteen-fifties. The scientists found that population of large fish like tuna; swordfish and cod have dropped by ninety percent in the past fifty years.
The study took ten years. The researchers gathered records from fishing businesses and governments around the world. The magazine Nature published the findings.
The scientists say the common method called longline fishing is especially damaging to populations of large fish. This method involves many fishing lines connected to one boat. These wires can be close to one-hundred kilometers long. They hold thousands of sharp metal hooks to catch fish.
Longline fishing is especially common in the Japanese fishing industry. Records showed that Japanese boats used to catch about ten fish for every one-hundred hooks. The study says longline fishing boats now might catch one fish per hundred hooks.
The scientists say industrial fishing can destroy groups of fish much faster than in the past. The study suggests that whole populations can disappear almost completely from new fishing areas within ten to fifteen years.
Ransom Myers of Dalhousie University in Nova Scotia led the study with Boris Worm of Dalhousie and the University of Kiel in Germany. Mister Worm says the destruction could lead to a complete re-organization of ocean life systems. Mister Meyers says the decreased number of large fish is not the only worry. He says even populations that are able to reproduce do not get the chance to live long enough to grow as big as their ancestors(祖先). He says not only are there fewer big fish, they are smaller than those of the past.
American government scientists say even with the best efforts to protect fish populations, decreases are to be expected.
【小题1】Where is the passage probably taken from?
| A．A story book. |
| B．A business magazine. |
| C．An environment report. |
| D．An economic survey. |
| A．longline fishing method is used |
| B．sea water is getting polluted |
| C．mankind destroys the environment |
| D．governments don’t make the best efforts |
| A．Today’s “large”fish are smaller than those of the past. |
| B．Longline boats now might catch fewer fish every one-hundred hooks. |
| C．Fish even able to reproduce don’t have the chance to live longer. |
| D．Japanese boats could catch about ten fish for every 100 hooks. |
| A．Discoveries Canadian Scientists Have Made |
| B．Japanese Fishing Industry |
| C．Losses of Big Fish |
| D．Modern Fishing Methods |
| A．In the 1960s. | B．In the 1970s. | C．In the 1980s. | D．In the 1990s. |