Previously, the sack-like rabbit appendix was thought to serve primar

游客2024-01-11  16

问题            Previously, the sack-like rabbit appendix was thought to serve primarily as
       a reservoir for the bacteria involved in hindgut fermentation, an explanation
       that failed to account for the absence of an appendix in other animals with
Line    similar digestive systems or for its presence in humans. Microscopic research
(5)      revealed that the appendix contains a significant amount of lymphoid tissue,
       similar aggregates of which tissue occur in other areas of the gastrointestinal
       tract. These are involved, possibly, in the body’s ability to recognize foreign
       antigens in ingested material, but the evidence is inconclusive, to the extent
       that scientists have long discounted the human appendix as a "vestigial" organ.
(10)         However, a growing body of evidence suggests that the appendix, far from
       being a "vestigial organ", has a significant function as a part of the body’ s
       immune system. The appendix achieves its greatest development shortly after
       birth, when immune response is first developing, then regresses with age,
       when the immune response mediated by the appendix may relate to such
(15)     inflammatory conditions as ulcerative colitis, which in adults necessitates the
       organ’s surgical removal. [br] It can be inferred from the passage that the author of the passage would be most likely to agree with which of the following assertions about the appendix?

选项 A、Scientists have ruled out the possibility that the appendix is involved in hindgut fermentation in all species, including rabbits.
B、As an organ, the appendix is more useful to the immune response of human beings in their first development than later in life.
C、The human appendix contains greater amounts of lymphoid tissue than the aggregates of which that are found in other areas of the gastrointestinal tract.
D、The appendix in a human child is generally less well developed than the appendix in a human adult.
E、The presence of the appendix in humans suggests that the human digestive process resembles the rabbit digestive process more than that of other animal species.

答案 B

解析
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