To most people，giraffes are merely adorable，long-necked animals that rank near the top of a zoo visit.But to cardiovascular （心血管的）scientists，there's even more to love.Giraffes，as it turns out，have solved a problem that kills millions of people every year：high blood pressure.
Giraffes have sky-high blood pressure because of their sky-high heads that，in adults，rise about six meters above the ground-a long，long way for their hearts to pump blood upwards against gravity.To have a blood pressure of 110/70 in the brain-normal for a large animal-giraffes need a blood pressure of about 220/180 in the heart.It doesn't vex the giraffes，but pressure like that would cause all sorts of problems for people，from heart failure to kidney failure to abnormal ankles and legs.
When biologist Barbara Natterson-Horowitz examined giraffes' hearts，she found that their left ventricles （心室） did get thicker，but without fibrosis（纖維化），which is a health problem associated with heart disease and would occur in people.She also found that giraffes have variants of five genes related to fibrosis.In keeping with the findings，other researchers who examined giraffe genes found several giraffe-specific gene variants related to cardiovascular development and steady blood pressure.And in 2021，another research group reported giraffe-specific variants of genes involved in fibrosis.
And the giraffe has another trick to avoid heart failure：The ventricular filling period of the heartbeat is extended，Natterson-Horowitz found.This allows the heart to pump more blood with each beat，allowing giraffes to run hard despite their thicker heart muscle.
Natterson-Horowitz is now turning her attention to another problem giraffes seem to have solved：high blood pressure during pregnancy.For people，this can lead to severe illnesses.Yet giraffes seem to do just well.Natterson-Horowitz and her team are hoping to find out if they have unique adaptations that allow this.
（1）What does the underlined word "vex" in paragraph 2 mean？ DD
A．Frighten.
B．Interest.
C．Warn.
D．Disturb.
（2）Why can giraffes resist fibrosis？ CC
A．They have high blood pressure.
B．They have slower heartbeats.
C．They have specific gene variants.
D．They have thicker left ventricles.
（3）What will Natterson-Horowitz and her team focus on in the future？ BB
A．What causes giraffes' gene variants.
B．What makes pregnant giraffes well.
C．Why pregnant women suffer from illnesses.
D．Why giraffes have unique adaptations.
（4）Which is the best title for the text？ AA
A．Cardiovascular Secrets of Giraffes
B．Studies on Heart Fibrosis of Giraffes
C．Health Effects of Giraffes' Long Necks
D．Reasons for Man's High Blood Pressure
【考點(diǎn)】說明文．
【答案】D；C；B；A
【解答】
【點(diǎn)評】
聲明：本試題解析著作權(quán)屬菁優(yōu)網(wǎng)所有，未經(jīng)書面同意，不得復(fù)制發(fā)布。
發(fā)布：2024/5/27 14:0:0組卷：5引用：4難度：0.6
相似題
-
1．It is widely believed that biodiversity（生物多樣性）is promoted to save species.But in reality species exist only as part of ecosystems and cannot survive unless their ecosystems are protected along with as much as possible of the diversity they contain.
Protecting habitats（棲息地）is important for keeping biodiversity.In 2003，over 102，000 habitats covering nearly 19 million square kilometres，or 11.5% of the world's land surface，were under some form of protection.Though this is a great improvement since 1962，when just 1，000 protected habitats were listed，it is still not considered enough to stop the ecocide that is endangering the world's biodiversity.
For a number of environmentalist，protecting the world's 25 biodiversity hotspots（熱點(diǎn)地區(qū)）is critical to saving habitats and species.But many hotspots are endangered already，having lost up to three-quarters of their original plants.
The poor state of most biodiversity hotspots results directly from population growth and migration（遷移） into these areas.A study found that by the mid-1990s around 1.1 billion people lived in these hotspots.Moreover，the annual population growth rate in these areas was 1.8%，higher than the global average of 1.4%.The PAI report concluded that human-related environmental changes will continue to put pressure on hotspots.Therefore，keeping biodiversity requires paying close attention to population size.
Protecting hotspots is not simply a matter of putting up fences and employing guards.The best results are achieved when local people are educated about the value of wildlife，and actually gain a share of the benefits from eco-tourism.Only then do they have a chance to see the benefits of protecting hotpots.
（1）What can we infer from paragraph 1？
A．The loss of any species can affect humans.
B．Endangered species are paid more attention to by humans.
C．Species can still survive when their ecosystems are destroyed.
D．Ecosystem protection is as important as diversity protection.
（2）What does the underlined word "ecocide" in paragraph 2 mean？
A．Ecosystem protection.
B．Reduction of the number of species.
C．Serious damage to habitats.
D．Habitats protection.
（3）What's the direct cause of the terrible state of the hotspots？
A．Population growth in hotpots.
B．Migration out of these areas.
C．Global warming.
D．The global average population growth rate.
（4）What's the author's opinion on protecting the hotspots？
A．It's simple to carry out.
B．It leads to the increase of tourists.
C．It's closely connected with local people.
D．It suggests that the local people are well educated.發(fā)布：2025/1/6 16:30:6組卷：0引用：1難度：0.5 -
2．Most of us spend our lives seeking the natural world.We go fishing，sit in the garden，have a picnic，live in the suburbs or go to the seaside.The most popular leisure activity in Britain is going for a walk.When joggers jog，they don't run on the streets.Every one of them tends to go to the park or the river.
But despite this，our children are growing up naturedeprived（剝奪）.I spent my boyhood climbing trees.These days，children are robbed of the ancient freedom，due to problems like crime，traffic，the loss of the open space and strange new ideas about what is best for children，that is to say，things that can be bought，rather than things that can be found.
The truth is to be found elsewhere.A study in the US：families had moved to better housing and the children were assessed for ADHD—Attention Deficit Hyperactivity Disorder（注意力缺陷多動癥）.Those whose accommodation had more natural views showed an improvement of 19%；those who had the same improvement in material surroundings but no nice view improved just 4%.
ADHD is one of the great problems of modern childhood.One study after another indicates that contact with nature gives huge benefits to ADHD children.However，we spend money on drugs rather than on green places.
The life of old people is measurably better when they have access to nature.The increasing concern for the growing population of old people is in quality rather than quantity of years.And study after study finds that a garden is the single most important thing in finding that quality.Even problems with crime and aggressive behaviour are reduced when there is contact with the natural world.
We need the wild world.It is essential to our wellbeing，our health and our happiness.
（1）According to the author，people enjoyto seek nature.
A．jogging on the street
B．running in the gym
C．shopping in the supermarket
D．sitting in the garden
（2）From the second paragraph，we can see that.
A．Children don't want to approach nature
B．children probably spend less time in nature nowadays
C．climbing trees will certainly do good to the children
D．children tend to be happier as a result of their material satisfaction
（3）In what way do people benefit from their contact with nature？
A．Children with ADHD can be cured.
B．Children's performance at school is greatly improved.
C．Problems with crime and violent behavior will easily be solved.
D．A garden nearby improves the quality of old people's life.
（4）what is the main idea of this passage？
A．Access to nature improves our life.
B．Nature treats children for ADHD.
C．Getting close to nature reduces crime.
D．Man can't live without natural areas.發(fā)布：2025/1/6 16:30:6組卷：0引用：1難度：0.5 -
3．New editions of Roald Dahl's classic books，such as Charlie and the Chocolate Factory and Matilda，are now available in bookstores.Some passages relating to weight，mental health，gender and race were changed.The changes made by Puffin Books，a division of Penguin Random House，first were reported by Britain's Daily Telegraph newspaper.
The changes to Dahl's books mark the latest debate over cultural sensitivity.Those who support updates seek to protect young people from cultural，ethnic and gender stereotypes in literature and other media.Critics complain that revisions to suit 21st century sensibilities risk weakening the genius of great artists and preventing readers from facing the world as it is.
The Roald Dahl Story Company controls the rights to the books.The company said it worked with Puffin Books to review the texts because it wanted to ensure that"Dahl's wonderful stories and characters continue to be enjoyed by all children today."
Inclusive Minds，a group that is working to make children's literature more inclusive and accessible，reviewed the language in a partnership effort with Puffin Books.Inclusive language avoids terms that could be seen as excluding specific groups of people.Any changes were"small and carefully considered，"the company said.
"When publishing new print runs of books written years ago，it's not unusual to review the language used alongside updating other details，including a book's cover and page layout，"the company said their guiding principle throughout had been to maintain the storylines，characters，and the spirit of the original text.
PEN America，a community of some 7，500 writers that advocates for freedom of expression，said it was"alarmed"by reports of the changes to Dahl's books.Suzanne Nossel，chief executive of PEN America，commented on Twitter.She said if we try"to correct for sensing slights （怠慢） instead of allowing readers to receive and react to books as written，we risk distorting the work of great authors and clouding the essential lens （透鏡） that literature offers on society."
Laura Hackett is a childhood Dahl fan who is now deputy literary editor of London，England's Sunday Times newspaper.She had a more personal reaction to the news."The editors at Puffin should be ashamed of the botched surgery they've carried out on some of the finest children's literature in Britain，"she wrote."As for me，I'll be carefully putting away my old，original copies of Dahl's stories，so that one day my children can enjoy them in their full，nasty and colorful glory."
（1）What is the reason for the changes to Dahl's books？
A．To make Dahl's books more enjoyable.
B．To review the language used and add details.
C．To remove words that show disrespect to some people.
D．To keep the storylines，characters，and the spirit of the original text.
（2）What might the underlined word in Paragraph 6 probably mean？
A．Preventing.
B．Appreciating.
C．Understanding.
D．Misrepresenting.
（3）Which of the following may Laura Hackett agree？
A．The new version of the books is worth collecting.
B．The original version of the books are more valuable.
C．The original books weaken the genius of great artists.
D．The new version allows readers to receive books as written.
（4）What might be the proper title of the passage？
A．New Changes to Roald Dahl Books Start Argument
B．Different Opinions on New Editions of Classic Books
C．Authors or Publishers both Control the Right to Books
D．New Editions of Roald Dahl's Classic Books Available
（5）What is the purpose of the passage？
A．To persuade readers to buy Roald Dahl's classic books.
B．To entertain readers by the changes of Roald Dahl's books.
C．To recommend the new version of Roald Dahl's classic books.
D．To inform diverse views on the changes of Roald DahI's books.發(fā)布：2025/1/30 8:0:1組卷：1引用：1難度：0.4
相關(guān)試卷