Câu hỏi: Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer for each of the questions from 35 to 42
Lichens, probably the hardiest of all plants, livingwhere virtually nothing else can - on cold, rugged mountain peaks and also on sunbaked, desert rocks. They are usually the first life to appear on a mountainside that has been scraped bare by an avalanche.
Unlike other members of the plant kingdom, lichens are actually a partnership betweentwo plants. The framework of lichen is usually a network of minute hairlike fungus that anchors the plant. The other component Is an alga,similar to the green film of plant life that grows on stagnant pools,that Is distributed throughout the fungus. Being green plants, algae are capable of photosynthesis - that is, using energy from the Sun to manufacture their own fooD. The fungi arebelieved to supply water, minerals, and physical support to the partnership.
Lichens are famous for their ability to survive water shortage. When water is scarce,as is often the case on a mountain, lichens may become dormant and remain in that condition for prolonged periods of time. Some lichens can even grow where there is no rain at all, surviving on only occasional dew - the moisture that condenses on the surfaceof the plants at night. And, unlike most other plants, lichens are little affected by the strong ultraviolet rays found on mountainsides.
Lichens use little energy for they grow slowly. Some grow so slowly and are so old that they are called "time stains."You may find lichens that are centuries old; certain of these lichen colonies have been established for an estimated 2,000 years.
For decades, scientists wondered how the offspring of an alga and a fungus got together to form a new lichen asit seemed unlikely that they would just happen to encounter one another.
It was finally discovered that in many cases the two partners have never been separated, stalk-like "buds"that form on certain lichens are broken off by the wind or by animals; these roll or are blown to a new location.
The word prolonged in line 13 is closest in meaning to
A. precise
B. extended
C. approximate
D. regular
Lichens, probably the hardiest of all plants, livingwhere virtually nothing else can - on cold, rugged mountain peaks and also on sunbaked, desert rocks. They are usually the first life to appear on a mountainside that has been scraped bare by an avalanche.
Unlike other members of the plant kingdom, lichens are actually a partnership betweentwo plants. The framework of lichen is usually a network of minute hairlike fungus that anchors the plant. The other component Is an alga,similar to the green film of plant life that grows on stagnant pools,that Is distributed throughout the fungus. Being green plants, algae are capable of photosynthesis - that is, using energy from the Sun to manufacture their own fooD. The fungi arebelieved to supply water, minerals, and physical support to the partnership.
Lichens are famous for their ability to survive water shortage. When water is scarce,as is often the case on a mountain, lichens may become dormant and remain in that condition for prolonged periods of time. Some lichens can even grow where there is no rain at all, surviving on only occasional dew - the moisture that condenses on the surfaceof the plants at night. And, unlike most other plants, lichens are little affected by the strong ultraviolet rays found on mountainsides.
Lichens use little energy for they grow slowly. Some grow so slowly and are so old that they are called "time stains."You may find lichens that are centuries old; certain of these lichen colonies have been established for an estimated 2,000 years.
For decades, scientists wondered how the offspring of an alga and a fungus got together to form a new lichen asit seemed unlikely that they would just happen to encounter one another.
It was finally discovered that in many cases the two partners have never been separated, stalk-like "buds"that form on certain lichens are broken off by the wind or by animals; these roll or are blown to a new location.
The word prolonged in line 13 is closest in meaning to
A. precise
B. extended
C. approximate
D. regular
Prolong - extend - last longer: kéo dài
Đáp án B.