The summer beach season is prime time for shark attacks. It seems like sharks are attacking all the time .But that is something of an illusion. The number of attacks is very small.

   How does a shark hunt? Muscles and fins (鳍)give the shark its speed and maneuverability(灵活)in the water. A shark’s front fins act like the wings of a plane and let it “fly” through the water. The tail acts like a high-power propeller(推进器).

But the big thing that gives the shark its edge in the ocean is its sensory package. The package includes the shark’ eyes ,ears ,skin, nose and mouth, as well as electric sensing.

   A shark' nose is probably its most important sense.  If you were to put a single drop of blood in a swimming pool ,a great white shark could smell that. And they can tell the direction that the smell is coming from.

   Sharks handle their electric sensing using cell located in the head .Whenever something moves using its muscles , a shark can detect the electrical impulses( 脉冲)flowing to those muscles. A shark can electrically “see” anything that has muscles even if it is hiding or the water is not clear.

   Sharks even have vibration sensors in their skin. Even something moves near  the shark ,tubes pick up the pressure changes and hairs inside the tubes send signals to the brain . This extra sense allows a shark to turn quickly and attack again.

   When you put all these different senses together ,it makes the shark a nearly ideal hunter. A shark can detect prey from miles away and then use eyes ,electrosensing and movement sensing to home in .

   Strangely, sharks do not seem to use these senses to home in on people. The very low number of sharks tells us that sharks do not hunt people on a regular basis. On the other hand , people love to hunt sharks. Millions of sharks die every year. Without protection ,extinction is a definite possibility.

From the text ,we can know that____________________.

A. it is true that sharks are attacking all the time .

B. a shark can see anything that has muscles even if it is hiding

C. sharks deal with their electric sensing using cell located in the skin .

D. what gives the shark its speed and maneuverability is fins and muscles.

What gives the shark its edge in the ocean according to the text?

A. its muscles     B. its nose     C. Its sensory package   D. Its fins

The underlined phrase “home in on ”means_________.

A. swim            B. move           C. hunt          D. smell

In this text ,the writer implies that ________________.

A. there are many shark attacks.           B. humans beings should protect sharks

C. human beings dislike hunting sharks.     D. shark’s nose is very important.

Michael Fish may soon be replaced as a weather forecaster by something truly fishier---the shark(鲨鱼).

Research by a British biology student suggests that sharks could be used to predict storms.

Lauren Smith, 24, is close to completing her study on shark’s ability to sense pressure.

If her studies prove the theory, scientists may be able to monitor the behaviour of sharks to predict bad weather.

Miss Smith had previously studied the behaviour of lemon sharks in the Bahamas.

She then used their close relatives, lesser spotted dogfish, for further research at Aberdeen University.

Her work---thought to be the first of its kind to test the pressure theory ---- resulted from the observation that juvenile blacktip sharks(黑边鳍真鲨) off Florida moved into deeper water ahead of a violent storm in 2001.

Miss Smith said: “I’ve always been crazy about traveling and diving and this led me to an interest in sharks.”

“I was delighted to have been able to research in the area for my degree. I know there’s so much more we need to understand ---- but it certainly opens the way to more research.”

It has been discovered that a shark senses pressure using hair cells in its balance system.

At the Bimini Shark Lab in the Bahamas, Miss Smith fixed hi-tech sensors to sharks to record pressure and temperature, while also tracking them using GPS (Global Positioning System) technology.

In Aberdeen, she was able to study the effects of tidal(潮汐的) and temperature changes on dogfish----none of which were harmed. She also used a special lab which can mimic(模拟) oceanic pressure changes caused by weather fronts.

She is due to complete her study and graduate later this year. She says she will be looking for a job which will give her the chance to enrich her experience of shark research. 

The passage is most probably taken from _____.

A. a short-story collection

B. a popular science magazine

C. a research paper

D. a personal diary

What do we learn from the first four paragraph of the passage?

A. Sharks may be used to predict bad weather.

B. Sharks’ behaviour can be controlled.

C. Michael Fish is not qualified for his job.

D. Lauren Smith will become a weather forecaster.

Lauren Smith conducted her research by _______.

 A. removing hair cells from a shark’s balance system

 B. measuring the air pressure of weather fronts

 C. recording sharks’ body temperature

 D. monitoring sharks’ reaction to weather changes

What is the passage mainly about?

 A. A popular way of forecasting weather.

 B. A new research effort in predicting storms.

 C. Biologists’ interest in the secrets of sharks.

 D. Lauren Smith’s devotion to scientific research.

Sydney – A shark savaged a schoolboy’s leg while he was surfing with his father at a beach in Sydney on February 23.it was the third shark attack along the coast of Australia’s largest city in a month.

The 15 – year – old boy and his father were in the water off Avalon, on Sydney’s northern beaches, around dawn when he was attacked.The city’s beaches are packed with locals and tourists during the summer months.

“The father heard a scream and turned to see his son trashing (扭动) about in the water,” police said.“Fortunately, the shark swam away and the boy was helped to shore by his father.”

Lifesaving Club spokesman Nick Miller: “It got him around the top of his left leg and the father came and dragged him out of water.” He said the boy was bleeding heavily when he was brought to shore.“There was a lot of pain, as you can imagine”.The teenager was airlifted to hospital for treatment for leg injuries.

Police said the bites “cut through to the bone”, but the boy did not appear to have sustained any fractures (骨折).He was in a stable condition now.

Several beaches were closed after the attack.Water police and lifeguards were searching for the shark, while police hoped to identify its species by the shape of the bite marks.But they said it was too early to say what type of shark attacked the boy.“I don’t even know if he saw it,” Miller said.

Many shark species live in the waters off Sydney’s beaches, but attacks on humans are still relatively rare.However, there were two attacks on successive days earlier this month, one on a navy diver in Sydney harbor, not far from the famous Opera House, and the other on a surfer at the city’s world – famous Bondi beach.

Fishermen say shark numbers are on the rise.There is a ban on commercial fishing in the harbor, which has increased fish stocks.Marine experts also claim environmental protection has created a cleaner environment, attracting sharks closer to shore as they chase fish.Many shark species, including the Great White – the man – eater made famous in Steven Spielberg’s Jaws – are protected in Australian waters.

1.The report mainly tells us          

                 A.shark attacks on humans are on the rise

                 B.sharks attacked humans three times in one month

                 C.a boy was attacked by a shark at a Sydney beach

                 D.shark numbers are increasing in the waters off Sydney’s beaches

2.The underlined word “savaged” in the first paragraph probably means “        ”.

                 A.attracted   B.dragged     C.bit      D.packed

3.What do we know about the city of Sydney from the passage?

                 A.It is one of the largest cities in Australia.

                 B.Sydney harbor is not far from the famous Opera House.

                 C.There are many locals and tourists on its coast all year round.

                 D.There are few shark species in the waters off Sydney’s beaches.

4.About the injury of the boy we know that         

                 A.he was losing much blood when he was dragged out

                 B.he was very nervous when he was sent to hospital

                 C.he may be in danger of losing his leg

                 D.he was injured in the right leg

 

For photographers lacking training, experience and even the ability to click a shutter button, they produce remarkable pictures.Under the sea, deep in the woods and high in the sky, furry, feathery and leathery-skinned creatures are opening up vistas(远景)by taking cameras where no human can go.

This is the world of animal-borne imagine celebrated last month at a conference sponsored(supported) by the National Geographic Society for the 20th anniversary of its Crittercam, the device that started it all.

Since its debut(首次公开露面)in 1987 on the back of a turtle, the Crittercam and similar devices developed by others have grown smaller and more powerful.

“It’s more than just a camera now,” said Greg Marshall, the marine biologist and now filmmaker who invented the Crittercam.“We are now including more instruments to gather more data while at the same time reducing everything in size.”

The idea of attaching video cameras to animals came to Mr.Marshall in 1986 on a dive off Belize when a shark apporached him.When the animal quickly turned away, he noticed a shark with a sucker fish on its belly.He came up with the idea that putting a camera in place of the sucker fish would allow people to witness the shark’s behavior without disturbing it.

Crittercams have been attached to sharks, sea lions and other marine animals, and, more recently, to land animals.

Birds are a new addition, Mr.Marshall said.Dr.Christian Rutz of Oxford recently reported on tiny cameras called feathercams that monitor the crows in the South Pacific.It has discovered that crows are smarter than anyone knew they not only use twigs(嫩枝)and grass stems as tools to root out food, but they also save their favorite tools to use again.

Tracey L.Rogers, director of the Australian Marine Mammal Research Center in Sydney, said crittercam was a powerful tool in her work with leopard seals(豹斑海豹)in Antarctica.“In studying animals,” Dr.Rogers said at the meeting, “you want to see how our animal models align(与……一致)with reality.With a camera, you actually see what they do.You don’t have to guess.”

1.What’s the text mainly about?

A.The advantages of crittercam.

B.The development of Crittercams in the past 20 years.

C.How crittercam was invented.

D.How crittercam works.

2. What inspired Marshall to invent crittercam?

A.The sight of sucker fish clinging to a shark on a dive.

B.The thought of how to photograph animals better.

C.Noticing a shark eating a sucker fish on a dive.

D.Seeing a shark with a camera on its belly on a dive.

3. According to Dr.Rogers, crittercam ____.

A.can clear up all your doubts about animals

B.is the most powerful tool in studying animals

C.enabled her to observe the crows in the South Pacific closely

D.helped a lot with her research on leopard seals in Antarctica

4. All of the following are improvements of crittercams EXCEPT that ____.

A.the size is becoming smaller

B.more instruments are involved to gather more data

C.they allow researchers to see where and how animals live

D.they are able to be applied to smaller animals such as birds

 

 

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