Venus Flytraps A.From indigenous myths to John Wyndh

游客2024-01-09  11

问题                         Venus Flytraps
    A.From indigenous myths to John Wyndham’s Day of the Traffics and the off-Broadway musical Little Shop of Horrors, the idea of cerebral, carnivorous flora has spooked audiences and readers for centuries. While shrubs and shoots have yet to uproot themselves or show any interest in human beings, however, for some of earth’s smaller inhabitants—arachnids and insects—the risk of being trapped and ingested by a plant can be a threat to their daily existence. Easily the most famous of these predators is the Venus Flytrap, one of only two types of ’snap traps’ in the world. Though rarely found growing wild, the Flytrap has captured popular imagination and can be purchased in florists and plant retailers around the world.
B.Part of the Venus Flytrap’s mysterious aura begins with the title itself While it is fairly clear that the second-half of the epithet has been given for its insect-trapping ability, the origin of  ’Venus’ is somewhat more ambiguous. According to the International Carnivorous Plant Society, the plant was first studied in the 17th and 18th Centuries, when puritanical mores ruled Western societies and obsession was rife with forbidden human impulses and urges. Women were often portrayed in these times as seductresses and temptresses, and botanists are believed to have seen a parallel between the behavior of the plant in luring and devouring insects, and the imagined behavior of women in luring and  ’trapping’ witless men. The plant was thus named after the pagan goddess of love and money—Venus.
    C.The Venus Flytrap is a small plant with six to seven leaves growing out of a bulb-like stem. At the end of each leaf is a trap, which is an opened pod with cilia around the edges like stiff eyelashes. The pod is lined with anthocynin pigments and sweet-smelling sap to attract flies and other insects. When they fly in, trigger hairs inside the pod sense the intruder’s movement, and the pod snaps shut. The trigger mechanism is so sophisticated that the plant can differentiate between living creatures and non-edible debris by requiring two trigger hairs to be touched within twenty seconds of each other, or one hair to be touched in quick succession. The plant has no nervous system, and researchers can only hypothesize as to how the rapid shutting movement works. This uncertainty adds to the Venus Flytrap’s allure.
    D.The pod shuts quickly, but does not seal entirely at first; scientists have found that this mechanism allows miniscule insects to escape, as they will not be a source of useful nourishment for the plant. If the creature is large enough, however, the plant’s flaps will eventually meet to form an airtight compress, and at this point the digestive process begins. A Venus Flytrap’s digestive system is remarkably similar to how a human stomach works. For somewhere between five and twelve days the trap secretes acidic digestive juices that dissolve the soft tissue and cell membranes of the insect. These juices also kill any bacteria that have entered with the food, ensuring the plant maintains its hygiene so that it does not begin to rot. Enzymes in the acid help with the digestion of DNA, amino acids and cell molecules so that every fleshy part of the animal can be consumed. Once the plant has reabsorbed the digestive fluid—this time with the added nourishment—the trap re-opens and the exoskeleton blows away in the wind.
    E.Although transplanted to other locations around the world, the Venus Flytrap is only found natively in an area around Wilmington, North Carolina in the United States. It thrives in bogs, marshes and wetlands and grows in wet sand and peaty soils. Because these environments are so depleted in nitrogen, they asphyxiate other flora, but the Flytrap overcomes this nutritional poverty by sourcing protein from its insect prey. One of the plant’s curious features is resilience to flame—it is speculated that the Flytrap evolved this to endure through periodic blazes and to act as a means of survival that its competition lacks.
    F.While the Venus Flytrap will not become extinct anytime soon (an estimated 3-6 million plants are presently in cultivation)—its natural existence is uncertain. In the last survey, only 35,800 Flytraps were found remaining in the wild, and some prominent conservationists have suggested the plant be given the status of ’vulnerable’. Since this research is considerably dated, having taken place in 1992, the present number is considerably lower. The draining and destruction of natural wetlands where the Flytrap lives is considered to be the biggest threat to its existence, as well as people removing the plants from their natural habitat. Punitive measures have been introduced to prevent people from doing this. Ironically, while cultural depictions of perennial killers may persist, the bigger threat is not what meat-eating plants might do to us, but what we may do to them.
Questions 14-19
    Reading Passage 2 has six paragraphs, A-F.
    Which paragraph contains the following information?
    Write the correct letter, A-F, in boxes 14-19 on your answer sheet. [br] An overview of how the Flytrap eats its prey

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答案 D

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