题目内容

【题目】B

A new study, led by scientists at the American Museum of Natural History, shows that living sharks are actually quite advanced in evolutionary terms, despite having retained their basic "sharkiness" over millions of years. The research is published today in the journal Nature.

"Sharks are traditionally thought to be one of the most primitive surviving jawed vertebrates(脊椎动物). And most textbooks in schools today say that the internal jaw structures of modern sharks should look very similar to those in primitive shark-like fishes," said Alan Pradel, a postdoctoral researcher at the Museum and the lead author of the study. "But we've found that is not the case. "

The new study is based on an extremely well-preserved shark fossil collected by Ohio University professors Royal Mapes and Gene Mapes in Arkansas, where an ocean basin once was home to a diverse marine ecosystem. The fossilized skull of the new species, named Ozarcus mapesae. The heads of all fishes -- sharks included -- are segmented into the jaws and a series of arches that support the jaw and the gills(鳃). These arches are thought to have given rise to jaws early in the tree of life.

Because shark skeletons are made of cartilage(软骨), not bone, their fossils are very fragile and are usually found in flattened parts, making it impossible to study the shape of these internal structures. But the Ozarcus mapesae specimen(标本)was preserved in a nearly three-dimensional state, giving researchers a rare glimpse at the organization of the arches in a prehistoric animal.

"This beautiful fossil offers one of the first complete looks at all of the gill arches and associated structures in an early shark. There are other shark fossils like this in existence, but this is the oldest one in which you can see everything," said John Maisey, a curator in the Museum's Division of Paleontology and one of the authors on the study. "There's enough depth in this fossil to allow us to scan it and digitally dissect out the cartilage skeleton."

Working with scientists at the European Synchrotron, the ESRF, Pradel imaged the specimen with high-resolution x-rays to get a detailed view of each individual arch shape and organization. "We discovered that the arrangement of the arches is not like anything you'd see in a modern shark or shark-like fish," said Pradel. "Instead, the arrangement is fundamentally the same as bony fishes."

The authors say it's not unexpected that sharks -- which have existed for about 420 million years -- would undergo evolution of these structures. But the new work, especially when considered alongside other recent developments about early jawed vertebrates, has significant implications for the future of evolutionary studies of this group. "Bony fishes might have more to tell us about our first jawed ancestors than do living sharks," Maisey said.

【1】What does the underlined word that in Paragraph 1 refer to?

A. Living sharks are quite advanced in evolutionary terms.

B. Sharks have kept their basic sharkiness over millions of years.

C. The jaw structures of modern sharks are similar to those in fishes.

D. Sharks jaws have remained almost the same over millions of years.

【2】It is hard to study the internal jaw structures of ancient sharks because .

A. there are only a few shark fossils

B. shark skeletons are made of bones

C. their fossils are often in poor condition

D. their fossils are found in a nearly three-dimensional state

【3】According to Paragraph 4, the shark fossil used in the study is .

A. the only complete shark fossil

B. the oldest complete shark fossil

C. the only Ozarcus mapesae specimen

D. the biggest Ozarcus mapesae specimen

【答案】

【1】D

【2】C

【3】B

解析一项针对古鲨鱼化石的研究为骨进化的研究指明了方向。

【1】D代词指代题根据第二段中的Sharks are traditionally thought to be one of the most primitive surviving jawed vertebrates…the internal jaw structures of modern sharks should look very similar to those in primitive shark-like fishes可知,划线词指代鲨鱼的骨在进化过程中基本未变。

【2】C细节理解题。根据第四段中的their fossils are very fragile and are usually found in flattened parts可知选C项。

【3】B 细节理解题。根据第五段段中的“this is the oldest one in which you can see everything”可知正确答案为B项。

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【题目】阅读下面短文,掌握其大意,然后从1~15各题所给的A、B、C和D项中,选出最佳选项,并在答题卡上将该项涂黑。

As a general rule, all forms of activity lead to boredom when they are performed on a routine basis. As a matter of fact, we can see this principle at in people of all ages. For example, on Christmas morning, children are about playing with their new toys. But their interest soon off and by January those same toys can be found put in the basement. The world is full of stamp albums and unfinished models, each standing as a monument to someone’s passing . When parents bring home a pet, their child bathes it and brushes its fur. Within a short time, , the burden of caring the animal is handed over to the . Adolescent enter high school with great excitement but soon looking forward to graduation. The same is of the young adults going to the college. And then, how many adults, who complain about the long drives to work, drove for hours at a time when they first obtained their drivers’ ? Before people retire, they usually plan to do a lot of great things, which never had time while working. But soon after , the golfing, the fishing, the reading and all of the other pastimes become as as the jobs they left. And, like the child in January, they go searching for new .

【1】A. school B. home C. work D. night

【2】A. curious B. optimistic C. anxious D. excited

【3】A. cuts B. leaves C. wears D. takes

【4】A. away B. off C. out D. up

【5】A. newly-designed B. half- filled C. well-organized D. colorfully-printed

【6】A. friendship B. job C. time D. interest

【7】A. worriedly B. thankfully C. happily D. hurriedly

【8】A. however B. therefore C. besides D. thus

【9】A. friends B. parents C. relatives D. teachers

【10】A. aware B. afraid C. tired D. true

【11】A. carefully B. nervously C. bravely D. eagerly

【12】A. work B. position C. licenses D. certificate

【13A. retirement B. resign C. assignment D. graduation

【14】A. frustrating B. boring C. interesting D. annoying

【15】A. surroundings B. friends C. toys D. pets

【题目】D

I was no different from any other mother.

When my little boy, Skyler, was born, I longed for the day he would talk to me. My husband and I dreamed about the first sweet “Mama” or “Dada.” Every cry or coo was a small glimpse into my son’s mind.

My baby’s noises were even more precious to me because Skyler had been born with several health problems.

At first, the problems had delayed his development, but once they were safely behind us. I looked forward to my son’s first words. They didn’t come.

At age three, Skyler was diagnosed autistic, a developmental disability destined to affect his social and emotional well-being in his entire life. Skyler couldn’t talk and wouldn’t talk. I would probably never hear any words from him at all. In a store, I would hear a child calling “Mommy,” and I would wonder if that were what my little boy might sound like. I wondered how it would feel to hear my child call out for me.

But I could have learned to live with his silence if it weren’t for another hallmark characteristic of autism: Skyler formed no attachments. He didn’t want to be held, much preferring to lie in his bed or sit in his car seat. He wouldn’t look at me; sometimes, he even looked through me.

Once, when I took him to the doctor, we talked to a specialist who was my size, age and who had the same hair color. When it was time to go, Skyler went to her instead of me—he couldn’t tell us apart. When Skyler was three, he spent three days at Camp Courageous for disabled children in Iowa, and when he returned he didn’t even recognize me.

The pain was almost unbearable. My own son didn’t even know I was his mother.

I hid the pain, and we did the best we could for Skyler. We enrolled him in our local area educational agency preschool, where the teachers and speech pathologist worked hard to help Skyler connect with the world around him. They used pictures and computer voice-machines that spoke for him, and sign language. These devices gave me little glimpses of who Skyler was, even if he didn’t understand who I was. “He will talk,” the speech pathologist insisted, but inside, I had given up hope.

The one dream I couldn’t let go was to have Skyler understand that I was his mom. Even if I never heard him say, “Mom,” I wanted to see the recognition in his eyes.

The summer of Skyler’s fourth year was when it started. A smoldering ember of understanding in him sparked, and fanned by our efforts, steadily flamed. His first words were hardly recognizable, often out of context, never spontaneous. Then, slowly, he could point to an item and say a word. Then two words together as a request. Then spontaneous words. Each day, he added more and more recognizable words, using them to identify pictures and ask questions. We could see his understanding increase, till his eyes would seek out mine, wanting to comprehend.

“You Mom?” he said one day.

“Yes, Skyler, I’m Mom.”

He asked his teachers and caregivers: “You Mom?”

“No, Skyler, not Mom.”(原作者:陈德琪)“You my Mom?” he said back to me.

“Yes, Skyler, I’m your Mom.”

And finally, a rush of understanding in his eyes: “You my Mom.”

“Yes, Skyler, I’m your Mom.”

If those had been Skyler’s only words ever, they would have been enough for me: My son knew I was his mother.

But Skyler wasn’t done.

One evening I leaned against the headboard on Skyler’s bed, my arms wrapped around him. He was cozily tucked between my legs, our bodies warm and snug as I read to him from one of his favorite books—a typical affectionate scene between mother and son, but because of Skyler’s autism, one that I could never take for granted.

I stopped reading. Skyler had interrupted me, leaning back his head so he could look me in the eye.

“Yes, Skyler?”

And then the voice of an angel, the voice of my son: “I love you, Mom.”

【1】According to the description of the author, we can learn that Skyler .

A. could easily have a cold

B. usually preferred to stay alone

C. could only recognize his doctor

D. frequently lost temper

【2】The author felt the most heartbroken when .

A. Skyler was diagnosed with autism

B. a child in a store called her Mommy

C. she realized Skyler didnt know who she was

D. she found Skyler was born with several health problems

【3】What does the underlined sentence mean?

A. The author had little hope that Skyler would talk.

B. The author decided to give up the treatments for Skyler.

C. The author was disappointed with the speech pathologist.

D. The author strongly believed that Skyler would make progress.

【4】Which of the following is TRUE according to the passage?

A. Skyler traveled around the world with his teachers.

B. The family was so frustrated that they lost hope.

C. The author never heard Skyler say Mum.

D. Skylers language ablity grew little by little.

【5】From the last few paragraphs, we can infer that .

A. the author was grateful that her efforts paid off

B. Skyler could not only talk but also read

C. mom was the only word Skyler could say

D. the author had high expectations for Skyler

【6】Whats the best title for the passage?

A. Road to Speaking B. What is Autism?

C. A Caring Mother D. Talk to Kids

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