科学家把天竺葵的原生质体和香茅草的原生质体进行诱导融合,培育出的驱蚊草含有香茅醛,能散发出一种特殊的气味达到驱蚊且对人体无害的效果。下列关于驱蚊草培育的叙述中,错误的是( ) A .驱蚊草的培育属于细胞工程育种,其优点是能克服远缘杂交不亲和的障碍 B .驱蚊草的培育过程要用到纤维素酶、果胶酶、 PEG 试剂或离心、振动、电刺激等方法 C .驱蚊草的培育过程是植物体细胞杂交,不同于植物组织培养,无愈伤组织和试管苗形成 D .驱蚊草不能通过天竺葵和香茅草杂交而获得,是因为不同物种间存在生殖隔离
【简答题】DATE AND METHOD OF SHIPMENT:20 June,2007-30 June,2007 by sea; otherwise 1 July,2007-15 July,2007 on seller's account by air. (1) 翻译: (2) 该合同下的货能否在18 June,2007或18 July,2007装运,为什么?
【单选题】19 At 30 June 2004 a company’s allowance for receivables was $39,000. At 30 June 2005 trade receivables totalled $517,000. It was decided to write off debts totalling $37,000 and to adjust the allowan...
【单选题】On June 1st, Lucy & Bros received an order for 500 cupcakes. Lucy delivered the cupcakes to the client on June 25th. A $50 deposit was received on June 5th and the remaining $450 was paid on June 30th...