B
When people lose legs after accidents or illnesses, emergency care and artificial limbs(假肢)often allow them to walk again. Newts (蝾螈) in the same situation, on the other hand, can grow limbs back on their own! Scientists have known for a long time that certain animals can re-grow limbs, but they haven’t quite figured out how these creatures do it.
Researchers have now come up with some new ideas. Their work may give people the ability to re-grow lost limbs. The researchers started with two simple experiments:when you cut a newt’s leg at the ankle, only the foot grows back;when you cut off a leg at the very end, the whole leg grows back. In both cases, the re-growth begins with stem cells. Stem cells can develop into nearly any type of cell in the body.
How do a newt’s stem cells know when to grow only a foot and when to re-grow a whole leg?
This question relates to another mystery. In newt’s, a cut-off leg will grow back only if the nerve bundle(神经束)in it also grows back , but if something prevents the nerve bundle from growing, the stem cells at the wound won’t re-grow a new leg.
In its study, a British team focused on a protein called n-AG. When the team prevented nerves in a limb from growing, but added the n-AG protein to stem cells in the limb, the limb still re-grew. That protein seems to guide limb re-growth. People have proteins that are similar to n-AG. Further research into these materials may someday help human limbs recover by themselves.
40. In the experiments, the researchers cut off a newt’s foot or leg to find out _____.
A. what stem cells were                     B. whether they would grow back
C. how long it would take to re-grow    D. how they would re-grow
41. A newt will re-grow its leg if _____.
A. its ankle was cut off but the nerve bundle was good
B. its leg was cut off and the nerve bundle stopped growing
C. its leg was cut off and the nerve bundle could grow back
D. its ankle and the nerve bundle were cut off
42. What do the underlined words “these materials” refer to?
A. Nerve bundles and proteins.         B. Proteins similar to n-AG.
C. Stem cells and proteins.               D. Stem cells and nerve bundles.
43. The first sentence of the passage _____.
A. acts as a lead–in                       B. shows where researchers got their new ideas
C. states the author’s opinion           D. describes the result of researchers’ studies


D
Cellphone users in the United States have contributed more than $11 million to Haitian earthquake relief through text messages in what is being called as an unexpected mobile response to a natural disaster.
The Mobile Giving Foundation called it a “mobile-giving record” for funds raised for a single cause. Donations are rising swiftly, as former President Bill Clinton and other politicians urge the American people to give.
Jim Manis, chief officer of the organization helping to manage cellphone donations, said it was receiving up to 10,000 text messages per second. The foundation said more than $11 million has been donated.
Cellphone users can donate $5 to Haiti-born hip-hop musician Wyclef Jean’s Yele Haiti Earthquake Fund by texting the word “Yele” to 501501, or they can donate $10 to other nonprofit organizations, such as the American Red Cross, by texting the word “Haiti” to a specified number, like 90999.
The donation is charged to a user’s cellphone bill.
The American Red Cross said it has received more than $ 9 million in donations from more than 900,000 mobile phone users.
“It’s beyond our imagination that we’ve received this amount,” said spokeswoman Nadia Pontif.
Jean’s fund had raised $2 million via text messages, according to Give on the Go, Yele’s mobile application service provider.
The giving is also being fueled by the popularity of websites like Facebook and Twitter, where users are urging one another to make donations using cellphones.
Wireless carriers(无线运营商) Verizon Wireless, AT&T Inc., Sprint and T-Mobile USA, a unit of Deutsche Telekom AG, have waived(免收) fees for customers wishing to send mobile donations. Carriers are also letting users know they are not taking a cut of the donations.
“There are no text messaging fees and 100% of the $10 donation goes to the American Red Cross, and every carrier is working through a solution to push those funds out faster.” Verizon said in a statement.
68. A mobile phone user can donate some money to Haiti by texting the word _____ .
A. “Yele” to 501501 to donate $10                    B. “Haiti” to 90999 to donate $10
C. “Yele” or “Haiti” to 501501 to donate $ 5      D. “Haiti” to the American Red Cross to donate $ 5
69. The underlined word “fueled” in the ninth paragraph most probably means “_____ ”.
A. protected             B. discouraged      C. inspired             D. reflected
70. Which of the following statements is TRUE according to the passage?
A. Facebook and Twitter are two relief organizations from the USA.
B. Many American politicians force Americans to give donations to Haiti.
C. The American Red Cross expected to receive much more donations.
D. Carriers have promised not to take a share from the donation.
71.Which may be the best title for the passage?
A. U.S. Texting Raises $11 Million for Haiti Earthquake
B. An Unexpected Terrible Earthquake Hit Haiti
C. The American Red Cross Offers Help to Haiti
D. Wireless Carriers Donate $11 Million to Haiti

When people lose legs after accidents or illnesses, emergency care and artificial limbs(假肢)often allow them to walk again. Newts (蝾螈) in the same situation, on the other hand, can grow limbs back on their own! Scientists have known for a long time that certain animals can re-grow limbs, but they haven’t quite figured out how these creatures do it.
Researchers have now come up with some new ideas. Their work may give people the ability to re-grow lost limbs. The researchers started with two simple experiments:when you cut a newt’s leg at the ankle, only the foot grows back;when you cut off a leg at the very end, the whole leg grows back. In both cases, the re-growth begins with stem cells. Stem cells can develop into nearly any type of cell in the body.
How do a newt’s stem cells know when to grow only a foot and when to re-grow a whole leg?
This question relates to another mystery. In newt’s, a cut-off leg will grow back only if the nerve bundle(神经束)in it also grows back , but if something prevents the nerve bundle from growing, the stem cells at the wound won’t re-grow a new leg.
In its study, a British team focused on a protein called n-AG. When the team prevented nerves in a limb from growing, but added the n-AG protein to stem cells in the limb, the limb still re-grew. That protein seems to guide limb re-growth. People have proteins that are similar to n-AG. Further research into these materials may someday help human limbs recover by themselves.
40. In the experiments, the researchers cut off a newt’s foot or leg to find out _____.
A. what stem cells were                    B. whether they would grow back
C. how long it would take to re-grow    D. how they would re-grow
41. A newt will re-grow its leg if _____.
A. its ankle was cut off but the nerve bundle was good
B. its leg was cut off and the nerve bundle stopped growing
C. its leg was cut off and the nerve bundle could grow back
D. its ankle and the nerve bundle were cut off
42. What do the underlined words “these materials” refer to?
A. Nerve bundles and proteins.         B. Proteins similar to n-AG.
C. Stem cells and proteins.              D. Stem cells and nerve bundles.
43. The first sentence of the passage _____.
A. acts as a lead–in                      B. shows where researchers got their new ideas
C. states the author’s opinion           D. describes the result of researchers’ studies

D

Cellphone users in the United States have contributed more than $11 million to Haitian earthquake relief through text messages in what is being called as an unexpected mobile response to a natural disaster.

The Mobile Giving Foundation called it a “mobile-giving record” for funds raised for a single cause. Donations are rising swiftly, as former President Bill Clinton and other politicians urge the American people to give.

Jim Manis, chief officer of the organization helping to manage cellphone donations, said it was receiving up to 10,000 text messages per second. The foundation said more than $11 million has been donated.

Cellphone users can donate $5 to Haiti-born hip-hop musician Wyclef Jean’s Yele Haiti Earthquake Fund by texting the word “Yele” to 501501, or they can donate $10 to other nonprofit organizations, such as the American Red Cross, by texting the word “Haiti” to a specified number, like 90999.

The donation is charged to a user’s cellphone bill.

The American Red Cross said it has received more than $ 9 million in donations from more than 900,000 mobile phone users.

“It’s beyond our imagination that we’ve received this amount,” said spokeswoman Nadia Pontif.

Jean’s fund had raised $2 million via text messages, according to Give on the Go, Yele’s mobile application service provider.

The giving is also being fueled by the popularity of websites like Facebook and Twitter, where users are urging one another to make donations using cellphones.

Wireless carriers(无线运营商) Verizon Wireless, AT&T Inc., Sprint and T-Mobile USA, a unit of Deutsche Telekom AG, have waived(免收) fees for customers wishing to send mobile donations. Carriers are also letting users know they are not taking a cut of the donations.

“There are no text messaging fees and 100% of the $10 donation goes to the American Red Cross, and every carrier is working through a solution to push those funds out faster.” Verizon said in a statement.

68. A mobile phone user can donate some money to Haiti by texting the word _____ .

A. “Yele” to 501501 to donate $10                    B. “Haiti” to 90999 to donate $10

C. “Yele” or “Haiti” to 501501 to donate $ 5      D. “Haiti” to the American Red Cross to donate $ 5

69. The underlined word “fueled” in the ninth paragraph most probably means “_____ ”.

A. protected             B. discouraged      C. inspired             D. reflected

70. Which of the following statements is TRUE according to the passage?

A. Facebook and Twitter are two relief organizations from the USA.

B. Many American politicians force Americans to give donations to Haiti.

C. The American Red Cross expected to receive much more donations.

D. Carriers have promised not to take a share from the donation.

71.Which may be the best title for the passage?

A. U.S. Texting Raises $11 Million for Haiti Earthquake

B. An Unexpected Terrible Earthquake Hit Haiti

C. The American Red Cross Offers Help to Haiti

D. Wireless Carriers Donate $11 Million to Haiti

 

When people lose legs after accidents or illnesses, emergency care and artificial limbs(假肢)often allow them to walk again. Newts (蝾螈) in the same situation, on the other hand, can grow limbs back on their own! Scientists have known for a long time that certain animals can re-grow limbs, but they haven’t quite figured out how these creatures do it.

Researchers have now come up with some new ideas. Their work may give people the ability to re-grow lost limbs. The researchers started with two simple experiments:when you cut a newt’s leg at the ankle, only the foot grows back;when you cut off a leg at the very end, the whole leg grows back. In both cases, the re-growth begins with stem cells. Stem cells can develop into nearly any type of cell in the body.

How do a newt’s stem cells know when to grow only a foot and when to re-grow a whole leg?

This question relates to another mystery. In newt’s, a cut-off leg will grow back only if the nerve bundle(神经束)in it also grows back , but if something prevents the nerve bundle from growing, the stem cells at the wound won’t re-grow a new leg.

In its study, a British team focused on a protein called n-AG. When the team prevented nerves in a limb from growing, but added the n-AG protein to stem cells in the limb, the limb still re-grew. That protein seems to guide limb re-growth. People have proteins that are similar to n-AG. Further research into these materials may someday help human limbs recover by themselves.

40. In the experiments, the researchers cut off a newt’s foot or leg to find out _____.

A. what stem cells were                    B. whether they would grow back

C. how long it would take to re-grow    D. how they would re-grow

41. A newt will re-grow its leg if _____.

A. its ankle was cut off but the nerve bundle was good

B. its leg was cut off and the nerve bundle stopped growing

C. its leg was cut off and the nerve bundle could grow back

D. its ankle and the nerve bundle were cut off

42. What do the underlined words “these materials” refer to?

A. Nerve bundles and proteins.         B. Proteins similar to n-AG.

C. Stem cells and proteins.              D. Stem cells and nerve bundles.

43. The first sentence of the passage _____.

A. acts as a lead–in                      B. shows where researchers got their new ideas

C. states the author’s opinion           D. describes the result of researchers’ studies

 

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