Look at the ten statements for this part. You will hear a passage about "The Number of Genes ". You will listen to it twice.

admin2019-01-04  40

问题     Look at the ten statements for this part.
    You will hear a passage about "The Number of Genes ". You will listen to it twice.
    Decide whether you think each statement is right(R), wrong(W)or not mentioned(NM).
    Mark your answers on the Answer Sheet.
The Novartis scientists did a new study and found the number could be forty thousand.
Look at the ten statements for this part.
    You will hear a passage about "The Number of Genes ". You will listen to it twice.
    Decide whether you think each statement is right(R), wrong(W)or not mentioned(NM).
    Mark your answers on the Answer Sheet.
                Number of Human Genes Questioned
    Scientists are questioning a widely reported finding from the first detailed study of the human gene map. The scientists dispute the findings that humans have only about thirty thousand genes. The new report suggests the true number could be much greater. Some believe that humans have more than one hundred thousand genes.
    The issue seemed to be settled last February. That is when two competing teams of scientists published their efforts to map the position of every human gene. A private American company called Celera Genomics published one of the genetic maps. An international group called the Human Genome Project prepared the other. Each group of scientists estimated that humans have about thirty thousand genes. That is about two times as many genes as some insects.
    That number came as a surprise to some people. They wondered how an organism as complex as a human could have so few genes. Some scientists believed the small number of genes was good news. It meant it would be easier to identify all the genes and understand how they work.
    In the new study, the Novartis scientists compared the two groups of human genes from the two genetic maps. They found that the two groups of scientists had identified two different sets of genes. Only about half the genes are common to both groups. The Novartis scientists say this means the number of human genes may be about four thousand.
    The director of the Human Genome Project, Francis Collins, said he would not be surprised if humans were found to have more than thirty thousand genes. Celera’s President, Craig Venter, notes that the process of discovering the real number is not simple. He said many of the genes noted in his company’s study had not been confirmed.
    The real number of human genes may not be known any time soon. Scientists say it probably will take years before we have a list of the genes that control human biology.
That is the end of Part 3. You now have 20 seconds to copy your answers on the Answer Sheet.

选项 A、Right
B、Wrong
C、Not Mentioned

答案A

解析
转载请注明原文地址:https://kaotiyun.com/show/En2d777K
0

最新回复(0)