搜题请搜索小程序“爱下问搜题”
问题 单项选择题

科学家从烟草花叶病毒（TMV）中分离出a、b两个不同品系，它们感染植物产生的病斑形态不同。下列4组实验（见下表）中，不可能出现的结果是（）

A.实验①

B.实验②

C.实验③

D.实验④

答案

参考答案：C

填空题

Kofi Annan says helping survivors of last week’ s earthquake and (1) in the Indian Ocean is (2) . The United Nations secretary- general says countries that have offered aid must (3) and provide it. The offers add up to around (4) dollars. United Nations officials say (5) of that is needed during the next six months. The concern about offers of international aid is (6) . For example, the earthquake in Barn, Iran, in (7) of 2003 killed more than (8) people. Countries and groups offered hundreds of millions of dollars (9) .The United Nations says it has (10) only about (11) dollars in aid received so far. Governments and organizations that offered help (12) that, however. On (13) Mr. Annan met with world leaders in Jakarta, Indonesia to discuss aid for (14) . The leaders discussed and (15) the idea of (16) owed by affected nations. But the leaders did not say they would do so. Some said that (17) to survivors would be more helpful. Representatives of (18) countries and international organizations attended the meeting in Jakarta. Officials say they will cooperate to develop (19) for the Indian Ocean and the (20) .
查看答案
填空题

暖季型草坪草主要包括狗牙根属、结缕草属、野牛草属、地毯草属、假俭草属、（）属、（）属和（）属等八个属的草坪草。
查看答案