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.
看题不仔细,文中的关系是:1T是一种只在细胞里会不断活跃分化的酶。---2骨髓细胞是例外因为它会不断分化造血----3癌细胞也是例外因为它分化的飞快。所有的答案都需要从这3点来推出,超出范围的就算错误答案。同时C是唯一3个点都提到的答案:T,骨髓,癌细胞
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