题干

下列关于造血干细胞和其分化形成的B细胞的叙述,正确的是(   )

A:造血干细胞分化形成B细胞的过程中,其全能性得到表现

B:B细胞属于高度特化的体细胞,不能再继续分化

C:在不发生变异的情况下,造血干细胞和B细胞中的核DNA完全相同

D:在不发生变异的情况下,造血干细胞和B细胞中的RNA完全不相同

上一题 下一题 0.0难度 选择题 更新时间:2019-12-30 07:43:22

答案(点此获取答案解析)

C

同类题3

阅读材料,从每题所给四个选项(A、B、C和D)中选出最佳选项。

Jack works in a bookstore. Here is a note from his boss, Ben. Jack will decide what books to order(订购) according to the notes and the information about the books.

Hi Jack,

    You must hand in the order list of books by the first working day of every month. The rules for choosing books are:

For textbooks:

※August is coming. We must have all textbooks, without thinking of other rules.

For books which are not textbooks:

※If more than 5 copies were sold last month, we choose them. But if there are 5 or more in stock(现货),we do not make an order.

※If the wholesale(批发) prices are higher than ﹩75, we don't choose them. And we don't order anything whose retail(零售) price is higher than ﹩100.

    The information about the books

Title: Homeland English

Publisher(出版社): Homeland Ltd

Wholesale price: ﹩110

Retail price: ﹩140

Textbook: Yes

Copies sold last month: 3

Copies in stock: 2

Title: How to Become Successful

Publisher: Founders Company Ltd

Wholesale price: ﹩25

Retail price: ﹩40

Textbook: No

Copies sold last month: 2

Copies in stock: 1

Title: Biology at a Glance

Publisher: New Times Publishing Ltd

Wholesale price: ﹩70

Retail price: ﹩95

Textbook: No

Copies sold last month: 18

Copies in stock: 3

Title: Good Health in 20 Days

Publisher: Oscar World Ltd

Wholesale price: ﹩50

Retail price: ﹩6 6

Textbook: No

Copies sold last month: 10

Copies in stock: 20