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2017年9月21日雅思阅读预测

中华考试网   2017-08-30   【

2017年9月21日雅思阅读预测

  题材 动物

  题型 单选+summary+判断题

  文章大意 主要讲了动物冬眠的情况等。

  Hibernation is a state of inactivity and metabolic depression in endotherms. Hibernation refers to a season of heterothermy that is characterized by low body temperature, slow breathing and heart rate, and low metabolic rate. Although traditionally reserved for "deep" hibernators such as rodents, the term has been redefined to include animals such as bears and is now applied based on active metabolic suppression rather than based on absolute body temperature decline. Many experts believe that the processes of daily torpor and hibernation form a continuum and utilize similar mechanisms. The equivalent during the summer months is known as aestivation. Some reptile species (ectotherms) are said to brumate, or undergo brumation, but any possible similarities between brumation and hibernation are not firmly established. Some insects, such as the wasp Polistes exclamans, hibernate by aggregating together in groups in protected places called hibernacula.

  Often associated with low temperatures, the function of hibernation is to conserve energy during a period when sufficient food is unavailable. To achieve this energy saving, an endotherm will first decrease its metabolic rate, which then decreases body temperature. Hibernation may last several days, weeks, or months depending on the species, ambient temperature, time of year, and individual's body condition.

  Before entering hibernation, animals need to store enough energy to last through the entire winter. Larger species become hyperphagic and eat a large amount of food and store the energy in fat deposits. In many small species, food caching replaces eating and becoming fat.[4] Some species of mammals hibernate while gestating young, which are either born while the mother hibernates or shortly afterwards.

  For example, the female polar bear goes into hibernation during the cold winter months to give birth to her offspring. She loses 15–27% of her pre-hibernation weight and uses stored fats for energy during times of food scarcity, or hibernation. It is evident that pregnant female polar bears significantly increase body mass prior to hibernation, and this increase is further reflected in the weight of their offspring. The fat accumulation prior to hibernation in female polar bears enables them to provide a sufficient and warm, nurturing environment for their newborns

  Newly Hatched birds 动物

  Fluoridation in the water 医疗健康

  Coastal sculpture 艺术

  Trade 发展史 20160109B 20120728

  Children and robot 科技

  Culture and Communication人文社科

  Ancient Greek Coins 人文社科

  Darkside of Technological Boom 科技

  Children's adults 文学

  Expert in musician 人文社科

  Skink in New Zealand 动物

  Solving an Arctic Mystery 人文社科 20160521 20141025

  Aquaculture in New Zealand农业

  The meaning of history study 人文社科

  Birds intelligence 动物

  Ocean power 能源

  Who should look after the child? 人文社科

  Paper money 发展史

  The tuatara-past and future 动物

  Gesture 人文社科

  Voynich manuscript 考古

  Food Addictive 工业

  Japan's ancient pottery 历史

  Fish communications 动物

  New Zealand Home Textile Craft 人文社科

  Sweet Trouble–Australia sugarcane industry农业

  The Grimme Fairy Tale 人文社科

  We have star performers 商业管理

  Blind to Change 心理学

  Tick Tock Body clock 生物 20161013 20121013

  The importance of being playful 人文社科

  When did music begin? 艺术 20160528 20130216

  Dust and American 环保

  Human Rights to animal 人文社科

  The power of music 艺术 20160109A 20131212*

  Odd and curious money 人文社科

  The history of Russian Ballet

  Unique golden textile 工业

  Consumer advertisement 商业管理

  Australia Parrots 动物

  Egypt‘s Sunken Treasures考古 20150509 20120331

  Alcohol fuel in England 能源

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