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大全44，07-08不明白中，答案怎么是这样？
It was once assumed that all living things could be divided into two fundamental and exhaustive categories. Multicellular plants and animals, as well as many unicellular organisms, are eukaryotic—their large, complex cells have a well-formed nucleus and many organelles. On the other hand, the true bacteria are prokaryotic cell (prokaryotic cell: 原核细胞), which are simple and lack a nucleus. The distinction between eukaryotes and bacteria, initially defined in terms of subcellular structures visible with a microscope, was ultimately carried to the molecular level. Here prokaryotic and eukaryotic cells have many features in common. For instance, they translate genetic information into proteins according to the same type of genetic coding. But even where the molecular processes are the same, the details in the two forms are different and characteristic of the respective forms. For example, the amino acid sequences of various enzymes tend to be typically prokaryotic or eukaryotic. The differences between the groups and the similarities within each group made it seem certain to most biologists that the tree of life had only two stems. Moreover, arguments pointing out the extent of both structural and functional differences between eukaryotes and true bacteria convinced many biologists that the precursors of the eukaryotes must have diverged from the common ancestor before the bacteria arose.
Although much of this picture has been sustained by more recent research, it seems fundamentally wrong in one respect. Among the bacteria, there are organisms that are significantly different both from the cells of eukaryotes and from the true bacteria, and it now appears that there are three stems in the tree of life. New techniques for determining the molecular sequence of the RNA of organisms have produced evolutionary information about the degree to which organisms are related, the time since they diverged from a common ancestor, and the reconstruction of ancestral versions of genes. These techniques have strongly suggested that although the true bacteria indeed form a large coherent group, certain other bacteria, the archaebacteria (archaebacteria: [复] n.[微]原始细菌( 一种不同于细菌和动植物细胞且要求完全厌氧条件并能产生甲烷的微生物)), which are also prokaryotes and which resemble true bacteria, represent a distinct evolutionary branch that far antedates the common ancestor of all true bacteria.
7. All of the following statements are supported by the passageEXCEPT:
(A) True bacteria form a distinct evolutionary group.
(B) Archaebacteria are prokaryotes that resemble true bacteria.
(C) True bacteria and eukaryotes employ similar types of genetic coding. C
(D) True bacteria and eukaryotes are distinguishable at the subcellular level.（E）
(E) Amino acid sequences of enzymes are uniform for eukaryotic and prokaryotic organisms.
C才对呀，怎么选E？ C在兰色high-light处，E在绿色处。C与原文相反呀，就是不support啊。而E中，与原文一致把，在文章从but even where the molecular processes are the same开始都是说difference的，这里怎么没support原文？不明白怎么答案是E？
8. The author’s attitude toward the view that living things are divided into three categories is best described as one of 如何看得出？
(A) tentative acceptance
(B) mild skepticism
(C) limited denial
(D) studious criticism（A）
(E) whole hearted endorsement
这个作者的态度题目，我在AE中犹豫，最后选了E。A从文章哪里可以看出来？？ |
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