题干

科学家用15N的硝酸盐作为标记物浸泡蚕豆幼苗,追踪蚕豆根尖细胞分裂情况,得到蚕豆根尖分生区细胞连续分裂数据如下图所示,下列叙述不正确的是
         

A:蚕豆根尖细胞分裂的一个细胞周期为19.3h

B:高尔基体、线粒体、核糖体在蚕豆根尖细胞分裂过程中活动旺盛

C:蚕豆根尖细胞的DNA分子结构稳定性较低的时期有2~19.3h、21.3~38.6h

D:基因重组可发生在19.3~21.3h、38.6~40.6h

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D

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    The booking notes of the play “The Age of Innocence”:

    Price: $10

    DISCOUNTS;

    Saver: $2 off any seat booked any time in advance for performances from Monday to Thursday. Savers are available for children under 16, over 60s and full-time students.

    Supersaver: Half-price seats are available for people with disabilities and one companion. It is advisable to book in advance. There is a maximum of eight wheelchair spaces available and one wheelchair space will be held until an hour before the show.

    Standby: Best available seats are on sale for $6 from one hour before the performance for people eligible (suitable) for Saver and Supersaver discounts and thirty minutes before for all other customers.

    Group Bookings: There is a ten percent discount for parties of twelve or more.

    School: School parties of ten or more can book $6 standby tickets in advance and will get every tenth ticket free.

    Please note: We are unable to exchange tickets or refund (退款) money unless a performance is cancel led due to unforeseen circumstances.

BOOKING:

    There are four easy ways to book seats for performance:

    In person: The Box Office is open Monday to Saturday, 10a. m.- 8pm.

    By telephone: Ring 01324976 to reserve your tickets or to pay by credit card (Visa, MasterCard and Amex accepted).

    By post: Simply complete the booking form and return it to Global Theatre Box Office.

    On line: Complete the on-line booking form at www. Satan fiedtheatre. com.