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NN们这么强调的框架、套路,怎么没人讨论?

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发表于 2011-1-26 18:08:05 | 只看该作者 回帖奖励 |倒序浏览 |阅读模式
在很多NN心经中,都强调了框架、架构、结构、套路的重要性,为什么很少有人讨论关于结构、套路的的话题呢?
今天,在总结此文套路结构的时候,又看不清楚了,希望大家指点、讨论~~
Passage 14


      Nearly a century ago, biologists found that if they

separated an invertebrate animal embryo into two parts

at an early stage of its life, it would survive and develop

as two normal embryos. This led them to believe that the

(5)cells in the early embryo are undetermined in the sense

that each cell has the potential to develop in a variety of

different ways. Later biologists found that the situation

was not so simple. It matters in which plane the embryo

is cut. If it is cut in a plane different from the one used

(10)by the early investigators, it will not form two whole

embryos.

   A debate arose over what exactly was happening.

Which embryo cells are determined, just when do they-

become irreversibly committed to their fates, and what

(15) are the “morphogenetic determinants” that tell a cell

what to become? But the debate could not be resolved

because no one was able to ask the crucial questions

in a form in which they could be pursued productively.

Recent discoveries in molecular biology, however, have

(20)  opened up prospects for a resolution of the debate.

Now investigators think they know at least some of the

molecules that act as morphogenetic determinants in

early development. They have been able o show that,

  in a sense, cell determination begins even before an egg

(25) is fertilized.  

  Studying sea urchins, biologist Paul Gross found

that an unfertilized egg contains substances that func-

tion as morphogenetic determinants. They are located

in the cytoplasm of the egg cell; i.e., in that part of the

(30) cell’s protoplasm that lies outside of the nucleus. In the

unfertilized egg, the substances are inactive and are not

distributed homogeneously. When the egg is fertilized,

the substances become active and, presumably, govern

the behavior of the genes they interact with. Since the

(35) substances are unevenly distributed in the egg, when the

fertilized egg divides, the resulting cells are different

from the start and so can be qualitatively different in

their own gene activity.

      The substances that Gross studied are maternal

(40) messenger RNA’s --products of certain of the maternal

genes. He and other biologists studying a wide variety

of organisms have found that these particular RNA’s

direct, in large part, the synthesis of histones, a class

of proteins that bind to DNA. Once synthesized, the

(45) histones move into the cell nucleus, where section of

DNA wrap around them to form a structure that resem-

bles beads, or knots, on a string. The beads are DNA

segments wrapped around the histones; the string is the

intervening DNA. And it is the structure of these beaded

(50)DNA strings that guides the fate of the cells in which

  they are located.

我的判断:
【套路】现象解释型

【逻辑简图】


提出现象:biologists found that if they separated an invertebrate animal embryo into two parts at an early stage of its life, it would survive and developas two normal embryos.(第一段第一句话)

错误解释:cells in the early embryo are undetermined in the sense that each cell has the potential to develop in a variety of different ways.(第一段第二句话)

质疑错误解释(第一段余下部分)

正确解释。。。后面不知道了。。。看不出来了

希望大家多讨论,相互帮助,共同进步!


【套路】现象解释型

【逻辑简图】


提出现象:biologists found that if they separated an invertebrate animal embryo into two parts at an early stage of its life, it would survive and developas two normal embryos.(第一段第一句话)

错误解释:cells in the early embryo are undetermined in the sense that each cell has the potential to develop in a variety of different ways.(第一段第二句话)

质疑错误解释(第一段余下部分)

正确解释。。。后面不知道了。。。看不出来了

希望大家多讨论,相互帮助,共同进步!
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