Muscle loss

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题目与答案

1. A description of a boy with unusual muscle strength
   • A
   • B
   • C
   • D
   • E
   • F

   答案：E

   原文定位：An experiment was conducted on a "superboy" who was normal at birth, lacking fat; by the age of five, he was excellent at weightlifting, lifting as much as three kilograms

   同义替换：「unusual muscle strength」↔「excellent at weightlifting」

2. A reference to the limitations of current treatments for muscle loss
   • A
   • B
   • C
   • D
   • E
   • F

   答案：B

   原文定位：Despite more than three decades of research into alternatives, the only way to stop such patients losing muscle is a long course of physiotherapy involving weight-bearing exercise, but this is of little use to the weakest and sickest, and in most cases, starts only after wasting has already set in. The use of anabolic steroids is being explored for some conditions. But these compounds have a huge range of effects on the body besides promoting muscle growth, some of them undesirable, and only appear to work well in conjunction with exercise

   同义替换：「limitations」↔「only work with」

3. A mention of a space agency's interest in anti-wasting research
   • A
   • B
   • C
   • D
   • E
   • F

   答案：G

   原文定位：The prospect of preventing atrophy is also of great interest to NASA, particularly in view of its much talked-about mission to Mars

   同义替换：「space agency」↔「NASA」，「anti-wasting research」↔「preventing atrophy」

4. A reason why space travel could lead to severe muscle loss
   • A
   • B
   • C
   • D
   • E
   • F

   答案：G

   原文定位：By the time astronauts reach the Red Planet, they can expect to lose up to 25 per cent of their muscle mass and be too weak to walk, let alone put on a space suit and carry out repairs

   同义替换：「travel」↔「reach」，「lead to severe muscle loss」↔「lose up to 25 per cent of their muscle mass」

5. An explanation of the biological process that causes muscle breakdown
   • A
   • B
   • C
   • D
   • E
   • F

   答案：D

   原文定位：The process involves the ubiquitin-proteasome pathway (UPP), the disposal machinery used to break down unwanted proteins in the cell (New Scientist, 17 December 2005, p. 36). Once the system has been activated, ubiquitin "destroy me" labels are added to muscle proteins. This breaks down the muscle filaments within cells, but does not change the number of muscle cells

   同义替换：「biological process」↔「the process involves the ubiquitin-proteasome pathway」，「causes muscle breakdown」↔「break down unwanted proteins」

6. A prediction of the wide-ranging benefits of anti-wasting drugs
   • A
   • B
   • C
   • D
   • E
   • F

   答案：F

   原文定位：Patients due to be confined to bed for more than a few days could be given the drug as soon as they begin bed rest to prevent muscle loss that would otherwise slow their recovery. Weaning patients off respirators would become easier as doctors could prevent wasting of the diaphragm. Disease need no longer lead to weakness, and broken bones would not mean long and painful physiotherapy sessions to rebuild muscle strength. And since loss of muscle mass is a major reason why we grow frail with age, an anti-wasting drug could keep older people on their feet and living independently for longer

7. Which TWO statements are true about the genes Atrogin1 and muRF1?
   • They are active in normal muscle tissue.
   • They are only active during muscle atrophy.
   • They prevent the breakdown of muscle proteins.
   • They are responsible for producing muscle filaments.
   • They code for enzymes that label proteins for destruction.

   答案：They are only active during muscle atrophy.,They code for enzymes that label proteins for destruction.

   原文定位：Atrogin1 and muRF1 were first described in 2001 and are the only two atrogenes active only during muscle atrophy;They code for ubiquitin ligases, the enzymes that attach the "destroy me" labels to proteins

8. The study of the "superboy" revealed he had very little 22_____ at birth.

   答案：fat

   原文定位：An experiment was conducted on a "superboy" who was normal at birth, lacking fat; by the age of five, he was excellent at weightlifting, lifting as much as three kilograms

   同义替换：「had very little」↔「lacking」

9. By the age of five, he could lift up to 23_____ kilogram(s).

   答案：three

   原文定位：An experiment was conducted on a "superboy" who was normal at birth, lacking fat; by the age of five, he was excellent at weightlifting, lifting as much as three kilograms

   同义替换：「up to」↔「as much as」

10. His mother works as a 24_____ ,

    答案：runner

    原文定位：The scientists found that this is closely related to his mother, who is a professional runner, and that his extended family has unusually strong abilities

    同义替换：「works」↔「professional」

11. and other members of his family have 25_____ great strength.

    答案：unusually

    原文定位：The scientists found that this is closely related to his mother, who is a professional runner, and that his extended family has unusually strong abilities

    同义替换：「other members of his family」↔「extended family」，「great strength」↔「strong abilities」

12. This condition is linked to a lack of 26_____ .

    答案：fat

    原文定位：An experiment was conducted on a "superboy" who was normal at birth, lacking fat; by the age of five, he was excellent at weightlifting, lifting as much as three kilograms