As is well known, the brain performs a very important _______, which controls the nerve system of the body.

 A. motion     B. action      C. function      D. fact

As is well known, the brain performs a very important _______, which controls the nerve system of the body.

 A. motion     B. action      C. function      D. fact

As is well known, the brain performs a very important _______, which controls the nerve system of the body.

 A. motion     B. action      C. function      D. fact

As I was driving out of the store parking lot, they crossed in front of me．My first reaction was filled with   36  at being delayed for a whole ten seconds．But I quickly became   37  when I realized that it was an elderly   38   ．
The man leaned on his   39  who walked in front of him．He not only used her for   40  but it was obvious that he was blind．The two of them  _41  as one—each needing the other to  42    in this fast-changing world．
That little example of true strength   43  my whole personal perception(理解) of life that day．Suddenly I wasn’t so   44  having to work a few extra hours on Saturdays．I had my    45 ，and I was still   46  young．
That picture of those two elderly people walking with dignity(尊严) and strength   47  me the entire week．My   48  wasn’t so bad after all．I had my health and a good job．I had a wonderful，         49  wife．I started to think—not only was I   50  to have these all, but so was that wonderful old couple，who，_51  the trials and sufferings of a long life，still had the love and support of each other to   52    them through this world．
There are so many people out there just like that couple．My wife and I sometimes   53 ourselves in our old age, walking arm in arm into the sunset. That image always gives us a    54  feeling．Just remember, none of us would be here if it wasn’t for our elders．We all should spend a little extra time and patience,   55  helping our elder friends．

As if there weren’t enough of them in the world already, scientists have succeeded in cloning flies. The alike fruit flies are the first insects ever cloned, says the Canadian team that created them. The question everyone asks is why anyone would want to clone flies in the first place. She hopes that the insects , which are very easy to experiment with , will help to adjust the cloning process in other animals and even in humans, where the technique is being researched to aid production of therapeutic (治疗的) stem cells.
In cloning, the DNA-containing nucleus of an adult cell is injected into an egg whose own nucleus(细胞核) has been removed. At the moment, the majority of cloned mice, sheep and other animals die before birth. It is thought this is because the adult DNA is not properly ‘reprogrammed’.
Using flies, researchers might discover genes that are important for this reprogramming, and that have matches in other animals. That is because it is relatively easy in flies to knock out the function of a single gene and then attempt cloning with these cells, which will test whether that gene is important. If such genes are confirmed, then in theory cloned mammalian embryos(晶胚) might be grown in selected solutions that change the activity of those genes to improve the technique’s success rate. Although some groups have attempted to clone insects before, Lloyd says this is the first time it has been successful. The team used a slight difference on the standard cloning process: they transferred nuclei taken from embryos rather than fully-grown adult cells. They sucked several nuclei (pl)out of developing fly embryos, and injected them into a fertilized(已受精的) fly egg. From over 800 early attempts, they cloned five adult insects, the group reports in the journal Genetics.
【小题1】The best title of this passage probably is _______.