Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 55 to 64. Although they are an inexpensive supplier of vitamins, minerals, and high-quality protein, eggs also contain a high level of blood cholesterol, one of the major causes of heart diseases. One egg yolk, in fact, contains a little more than two-thirds of the suggested daily cholesterol limit. This knowledge has caused egg sales to plummet...
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Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 55 to 64.
Although they are an inexpensive supplier of vitamins, minerals, and high-quality protein, eggs also contain a high level of blood cholesterol, one of the major causes of heart diseases. One egg yolk, in fact, contains a little more than two-thirds of the suggested daily cholesterol limit. This knowledge has caused egg sales to plummet in recent years, which in turn has brought about the development of several alternatives to eating regular eggs. One alternative is to eat substitute eggs. These egg substitutes are not really eggs, but they look somewhat like eggs when they are cooked. They have the advantage of having low cholesterol rates, and they can be scrambled or used in baking. One disadvantage, however, is that they are not good for frying, poaching, or boiling. A second alternative to regular eggs is a new type of egg, sometimes called 'designer' eggs. These eggs are produced by hens that are fed low-fat diets consisting of ingredients such as canola oil, flax, and rice bran. In spite of their diets, however, these hens produce eggs that contain the same amount of cholesterol as regular eggs. Yet, the producers of these eggs claim that eating their eggs will not raise the blood cholesterol in humans.
Egg producers claim that their product has been portrayed unfairly. They cite scientific studies to back up their claim. And, in fact, studies on the relationship between eggs and human cholesterol levels have brought mixed results. It may be that it is not the type of egg that is the main determinant of cholesterol but the person who is eating the eggs. Some people may be more sensitive to cholesterol derived from food than other people. In fact, there is evidence that certain dietary fats stimulate the body's production of blood cholesterol. Consequently, while it still makes sense to limit one's intake of eggs, even designer eggs, it seems that doing this without regulating dietary fat will probably not help reduce the blood cholesterol level.
What is the meaning of 'back up'?
A. reverse
B. advance
C. block
D. support
Frogs are amphibians, meaning that they can live both in and out of the water. All frogs lay their eggs in the water, and a female frog will lay thousands of eggs at a time. When the eggs hatch, (1)___babies__ come out are not frogs but rather tadpoles. Unlike frogs, tadpoles must spend all their time in the (2)___water__, being unable to breathe air at this point. Tadpoles also lack arms and legs, and have a tail which they (3)___disappear__ as they develop into frogs. Tadpoles are herbivours, which means that they only eat (4)__plants___. Specially, tadpoles eat algae, a water plant which can be harmful if there is too much of it. (5)___Therefore__, tadpoles are important to keep most ponds healthy.
As tadpoles develop into mature frogs, they develop the lungs which allow them to (6)___get___ air, and the arms and legs which allow them to move across (7)___ground __. At this point the mature frogs leave the ponds, (8)__so___ some species stay near the water for their entire lives. Mature frogs are carnivores, (9)__eating___ insects and small fish. Most frogs hunt using their long, sticky tongueto catch their prey. Some species of frogs have developed extremely strong poisons to defend (10)___themselves__ from their other animals.