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Scattered through the seas of the world are billions of tons of small plants
and animals called plankton. Most of these plants and animals are too small for
the human eye to see. They drift about lazily with the currents, providing a
basic food for many larger animals. Plankton has been described as the
equivalent of the grasses that grow on the dry land continents, and the
comparison is an appropriate one. In potential food value however, plankton far
outweighs that of the land grasses. One scientist has estimated that while
grasses of the world produce about 49 billion tons of valuable carbohydrates
each year. The sea’s plankton generates more than twice as much.
Despite its enormous food potential, little effort was made until recently to
farm plankton as we farm grasses on land. Now marine scientists have at last
begun to study this possibility, especially as the sea’s resources loom even
more important as a means of feeding an expanding world population.
No one yet has seriously suggested that “planktonburgers” may soon become
popular around the world. As a possible farmed supplementary food source,
however, plankton is gaining considerable interest among marine scientists.
One type of plankton that seems to have great harvest possibilities is a tiny
shrimplike creature called krill. Growing to two or three inches long, krill
provide the major food for the giant blue whale, the largest animal ever to
inhabit the Earth. Realizing that this whale may grow 100 feet and weigh 150
tons at maturity, it is not surprising that each one devours more than one ton
of krill daily.
Krill swim about just below the surface in huge schools sometimes miles wide,
mainly in the cold Antarctic. Because of their pink color, they often appear as
a solid reddish mass when viewed from a ship or from the air. Krill are very
high in food value. A pound of these crustaceans contains about 460
calories—about the same as shrimp or lobster, to which they are related.
If the krill can feed such huge creatures as whales, many scientists reason,
they must certainly be contenders as new food source for humans.
1.Which of the following best portrays the organization of the passage?
A.The author presents the advantages and disadvantages of plankton as a food
source.
B.The author quotes public opinion to support the argument for farming
plankton.
C.The author classifies the different food sources according to amount of
carbohydrate.
D.The author makes a general statement about plankton as a food source and
then moves to a specific example.
2.According to the passage, why is plankton regarded to be more valuable than
land grasses?
A.It is easier to cultivate.
B.It produces more carbohydrates.
C.It does not require soil.
D.It is more palatable.
3.Why does the author mention “planktonburgers”?
A.To describe the appearance of one type of plankton.
B.To illustrate how much plankton a whale consumes.
C.To suggest plankton as a possible food sources.
D.To compare the food values of beef and plankton.
4.What is mentioned as one conspicuous feature of krill?
A.They are the smallest marine animals.
B.They are pink in color.
C.They are similar in size to lobsters.
D.They have grass like bodies.
5.The author mentions all of the following as reasons why plankton could be
considered a human food source except that it is ___.
A.high in food value.
B.in abundant supply in the oceans.
C.an appropriate food for other animals.
D.free of chemicals and pollutants.
Passage 2
Questions 6 to 10 are based on the following passage:
The food we eat seems to have profound effects on our health. Although science has made enormous steps in making food more fit to eat, it has, at the same time, made many foods unfit to eat. Some research has shown tat 40 percent of cancer is related to the diet as well, especially cancer of the colon.
Different cultures ate more prone to get certain illnesses because of the food that is characteristic in these cultures. That food is related to illness is not a new discovery. In 1945, government researchers realized that nitrates and nitrites, commonly used to preserve color in meats, and other food additives,
caused cancer. Yet these carcinogenic additives remain in our food, and it becomes more difficult all the time to know which things on the packaging labels of processed food are helpful or harmful. The additives that we eat are not all so direct. Farmers often give penicillin to beef and poultry, and because of
this, penicillin has been found in the milk of treated cows. Sometimes similar drugs are administered to animals not for medicinal purposes, but for financial reasons. The farmers are simply trying to fatten the animals in order to obtain a higher price on the market. Although the Food and Drug Administration (FDA) has tried repeatedly to control these procedures, the practices continue.
6. How has science done a disservice to mankind?
A. Because of science, most of the foods we eat today are contaminated.
B. It has caused a lack of information concerning the value of food.
C. As a result of scientific intervention, some potentially harmful
substances has been added to our food.
D. The scientists have preserved the color of meats, but not of
vegetables.
7. What are nitrates used for?
A. They preserves flavor in packaged foods.
B. They preserve the color of meats.
C. They are the objects of research.
D. They cause the animals to become fatter.
8. The FDA has tried repeatedly to control .
A. the attempt to fatten the animals
B. the attempt to cure sick animals
C. the using of drugs to animals
D. the using of additives to preserve the dolor of food
9. The word “carcinogenic” means most nearly the same as .
A. trouble-making B. color-retaining
C. money-saving D. cancer-causing
10. Which of the following statements is NOT true?
A. Drugs are always given to animals for medical reasons.
B. Some of the additives in our food are added to the food itself and some
are given to the living animals.
C. Researchers have known about the potential hazards of the food additives
for over thirty-five years.
D. Food may cause forty percent of cancer in the world.
