- UID
- 655373
- 在线时间
- 小时
- 注册时间
- 2011-7-27
- 最后登录
- 1970-1-1
- 主题
- 帖子
- 性别
- 保密
|
Q31: TTGWD2-Q21: Telomeraseis an enzyme that is produced only in cells that are actively dividing. For this reason it is generally absent frombody tissues in adults. Bone marrow isan exception to this rule, however, since even in adults, bone marrow cellscontinually divide to replace old blood cells. Cancers are another exception, because their cells are rapidly dividing. Theinformation provided most strongly supports which of the following? A. Telomerase is the only enzyme that ispresent in cancerous cells but absent from cells that are not activelydividing.(原文内容无法解释“T是在癌细胞中唯一的酶”) B. In children, the only bodytissues from which telomerase is absent are those in which cells are notrapidly dividing. C. The presence of telomerase in bonemarrow is no indication of bone marrow cancer. D. Cancer of the bone marrow develops morerapidly than cancer growing in any other kind of adult tissue.(cancer发展的速度比较,无关) The level of telomerase production is always higher incancerous tissue than in noncancerous tissue.(癌细胞与非癌细胞中T产生的level比较,无关)
B选项,原文说T只出现在分裂活跃的细胞中,那么not rapidly dividing的细胞中就应该没有T。所以我觉得B好像对的(现在想想,是不是actively和rapidly概念有差异?不懂,求教哦!)
C选项,原文说骨髓中有T,癌细胞中有T,那么骨髓中T的出现,有可能是其本身的T,有可能是骨髓里有癌细胞的T。所以我觉得C说no indication太绝对了,骨髓中有T可能存在癌细胞。(是不是我想多了?求教哦!)
|
|