七年级广州英语周报第六期2021至2022学年上答案

七年级广州英语周报第六期2021至2022学年上答案

The evolution of the first animals may have oxygenated（供氧）Earth’s oceans. New research

led by the University of Exeter challenges the long held belief that oxygenation of the atmosphere and oceans was a precondition for the evolution of complex life forms.

The study, published in the journal Nature Geoscience, builds on the recent work of scientists in Denmark who found that sponges（海绵动物）一the first animals to evolve一require only small amounts of oxygen.

Professor Tim Lenton of the University of Exeter, who led the new study, said: “We argue that the evolution of the first animals could have played a key role in the widespread oxygenation of the deep oceans. This in turn may have facilitated the evolution of more complex, mobile animals.”

Critical to determining oxygen levels in the deep ocean is the balance of oxygen supply and demand. Demand for oxygen is created by the sinking of dead organic material into the deep ocean. The new study argues that the first animals reduced this supply of organic matter一both directly and indirectly.

Sponges feed by pumping water through their bodies, “digesting” the tiny particles of organic matter, and thus helping oxygenate the shelf seas that they live in. By oxygenating more of the bottom waters, the first animals actually increased the removal of the essential nutrient phosphorus（磷）in the ocean. This in turn reduced the productivity of the whole ocean ecosystem, lowering oxygen demand and thus oxygenating the deep ocean.

A more oxygen-rich ocean created ideal conditions for more complex mobile animals to evolve, because they have a higher requirement for oxygen. These included the first predatory（肉食的）animals with guts（内脏）that started to eat one another, marking the beginning of the type of food webs we are familiar with today.

Professor Simon Poulton of the University of Leeds, who is a co-author of the study, added: “This study provides a possible mechanism for ocean oxygenation without the requirement for a rise in atmospheric oxygen. It therefore questions whether the long-standing belief that there was a major rise in atmospheric oxygen at this time is correct. We simply don’t know the answer to this at present, which is ultimately key to understanding how our planet evolved to its current habitable state. Geochemists need to come up with new ways to explain oxygen levels on the early Earth.”

1.The underlined word “facilitated” in Para. 3 is closest in meaning to＿＿．

A. prevented B. promoted C. interrupted D. witnessed

2.From paragraphs 4 to 6, we can infer that＿＿．

A. phosphorus can keep the productivity of the ocean ecosystem

B. complex animals consume the same amount of oxygen as sponges

C. the sinking of dead organic material into the deep ocean produces oxygen

D. the existence of the first animals marks the beginning of modern food webs

3. From the last paragraph, we can learn Pro. Simon Poulton believes that＿＿．

A. their study gives a new explanation for the high oxygen content in the air

B．oxygen increased greatly in the air as the first animals oxygenated the oceans

C. their study answers the question of how the earth evolved to the present state

D. ocean oxygenation does not necessarily require a rise in atmospheric oxygen

4.The main purpose of the passage is to＿＿．

A. present the view that the first animals played an active role in oxygenating oceans

B. introduce two opposite opinions on how the first animals oxygenated oceans

C．analyze how atmospheric oxygen stepped up the evolution of oceanic animals

D. explain how oceanic oxygen determines the amount of atmospheric oxygen

七年级广州英语周报第六期2021至2022学年上答案试题答案

1.B

2.A

3.D

4.A

【解析】

试题分析: 本文讲述传统观点认为，地球上氧气含量的提高引发了原始动物的进化。然而，最新研究表明，早期海洋原始动物的进化可能为地球上的海洋提供了最初的氧气。

1.B 猜测词意。根据文中我们认为，原始动物的演化在大范围深层海水氧气的产生和积累过程中起了至关重要的作用。原始动物的进化或许反过来促进了更复杂、更活跃动物的出现可知选B项。

2.A 推断题。根据第五段提到This in turn reduced the productivity of the whole ocean ecosystem, lowering oxygen demand and thus oxygenating the deep ocean. 这种流失反过来降低了整个海洋生态系统的生物化学反应速率，从而减少了氧气的需求量，因此同样有助于深海氧气含量的增加，故选A项。

3.D 细节理解题。根据最后一段提到This study provides a possible mechanism for ocean oxygenation without the requirement for a rise in atmospheric oxygen. It therefore questions whether the long-standing belief that there was a major rise in atmospheric oxygen at this time is correct. 这项研究为不依赖于大气氧气含量上升的海水氧气化提供了合理解释。因此，长期以来人们所相信的在那个时候大气氧气含量大幅度上升的理论是否正确受到了怀疑，故选D项。

4.A 主旨大意。本文主要在讲述传统观点认为，地球上氧气含量的提高引发了原始动物的进化。然而，最新研究表明，早期海洋原始动物的进化可能为地球上的海洋提供了最初的氧气，故选A项。

考点:科普类阅读。

（湖南省怀化市2014年高三第二次模拟考试）21. For more information, please send an e-mail, ______ you can also include your advice to us.

A. when              B. where             C. which        D. that

七年级广州英语周报第六期2021至2022学年上答案试题答案

B

【解析】本题定语从句的先行词是an e-mail，后面的定语从句you can also include your advice to us句子结构很完整，所以使用关系副词where来引导，有时候where的先行词并不一定需要是表示地点的名词。句义：需要更多信息，请给我发邮件，在邮件里你可以把你给我们的建议也写上去。When的先行词必须是表示时间的名词。CD是关系代词，在句中不能做状语。故B正确。

【试题延伸】大多数定语从句对所修饰词的意思加以限制，表示“…的人（或东西）”，称为限定性定语从句。限定性定语从句，用来修饰和限定先行词，与先行词间的关系非常密切，它所修饰的先行词代表一个（些）或一类特写的人或物，从句用来说明先行词的性质、身份、特征等状况，如果去掉，则意思含混不清。限定性定语从句引导词有时可以省略。非限定性定语从句在形式上就与主句很松散，它与主句之间有一个逗点“，”隔开；它对其先行词没有限定、修饰的作用，只起补充、说明的作用。有时也用它来对全句进行补充、说明。即使将其去掉，也不会影响句子意思。非限定性定语从句引导词不可以省略。

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