Telomerase is an enzyme that is produced only in cells that are actively dividing. For this reason it is generally absent from body tissues in adults. Bone marrow is an exception to this rule, however, since even in adults, bone marrow cells continually divide to replace old blood cells. Cancers are another exception, because their cells are rapidly dividing.
The information provided most strongly supports which of the following?
Telomerase is the only enzyme that is present in cancerous cells but absent from cells that are not actively dividing.
In children, the only body tissues from which telomerase is absent are those in which cells are not rapidly dividing.
The presence of telomerase in bone marrow is no indication of bone marrow cancer.
Cancer of the bone marrow develops more rapidly than cancer growing in any other kind of adult tissue.
The level of telomerase production is always higher in cancerous tissue than in noncancerous tissue.
it is generally absent from body tissues in adults(在成年的人体组织中通常缺少核糖体蛋白酶)
核糖体蛋白酶只存在于分裂旺盛的细胞(换句话说:就是分裂不旺盛的细胞一定没有该酶)
B选项,儿童体内,没有该酶的组织是细胞不快速分裂的组织
错误一:文中是成年人,而选项中是儿童;
错误二:文中说分裂不旺盛的细胞一定没有该酶(即:分裂不旺盛可以→没有酶);选项中说的是没有该酶的组织是细胞不快速分裂的组织(即:没有该酶→细胞分裂不快速)
错误三:文中说的是旺盛分裂(actively dividing),选项中说的是快速分裂(rapidly dividing)
问:依据描述能得出什么结论。
A T是唯一的酶...., the only没说
B T是唯一不出现在哪里的酶, the only body tissues,没说
C 骨髓细胞里边出现T不一定就是得了骨髓癌。对的
D 骨髓癌比其他组织癌发展得快,没说
E T酶在癌组织中的产生速度要比非癌组织里要快,说不定骨髓细胞里边的level更高呢
D/E在文中讨论了liangge 例外,D/E都只考虑了cancer。
Telomerase is an enzyme that is produced only in cells that are actively dividing.(核糖体蛋白酶仅产在于旺盛分裂的细胞中)
it is generally absent from body tissues in adults(在成年的人体组织中通常缺少核糖体蛋白酶)
核糖体蛋白酶只存在于分裂旺盛的细胞(换句话说:就是分裂不旺盛的细胞一定没有该酶)
B选项,儿童体内,没有该酶的组织是细胞不快速分裂的组织
错误一:文中是成年人,而选项中是儿童;
错误二:文中说分裂不旺盛的细胞一定没有该酶(即:分裂不旺盛可以→没有酶);选项中说的是没有该酶的组织是细胞不快速分裂的组织(即:没有该酶→细胞分裂不快速)(telomerase 只在分裂旺盛的细胞中才会产生,但不代表所有分裂旺盛的细胞中都会产生telo➡️可能有的分裂旺盛的细胞,因为其他的限制原因没有产生telo ➡️ B选项错)
错误三:文中说的是旺盛分裂(actively dividing),选项中说的是快速分裂(rapidly dividing)
C选项:The presence of telomerase in bone marrow is [no indication of] bone marrow cancer. 骨髓中端粒酶的存在[不代表]骨髓癌。
➡️ telomerase 只在分裂旺盛的细胞中才会产生,但不代表所有分裂旺盛的细胞中都会产生telo
➡️可能有的分裂旺盛的细胞,因为其他的限制原因没有产生telo ➡️ B选项错
文中只说癌细胞rapidly dividing 并没有提到bm中产生的酶多。登录 或 注册 后可以参加讨论
c presence of telomerase in bone marrow可以是正常,也不排除有cancer,但是决定不能就此indicate bone marrow cancer
A: 不一定,癌细胞可能有其他酶,在不可分裂细胞中也没有
B: 全文没有提孩子
C: 是的,因为骨髓中也有端粒酶
D: 骨髓癌发展比其他组织癌症发展迅速不一定是因为骨髓中有端粒酶导致的
E: 酶的生产速率,没有提到
保证推理的正确性。