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【单选题】
氮是蛋白质的基本组成元素之一,所有生物体均含蛋白质,氮循环涉及到生物圈的全部领域,以下关于氮的生物体的吸收途径正确的是 ( ) (1)氮在大气中高达78%,可被生物体直接利用。 (2)通过高能固氮可将空气中游离的氮转化为硝酸盐和氨,而被植物吸收。 (3)所有植物都具有生物固氮作用,其根部根瘤菌可是氮气转变成硝酸盐,而被植物吸收。 (4)动物以植物为食而获得氮并转化为动物蛋白。 (5)动物死亡后,遗骸中的蛋白质被微生物分解成NH 4 + 、 NO 3 - 、 NH 3 ,又回到土壤中和水体中,被植物再次吸收。A.
⑴⑸
B.
⑶⑸
C.
⑵⑷⑸
D.
⑵⑷
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【简答题】运输市场营销战略
【单选题】In an abstract, the main procedures or the materials and equipment used to create the final result of the research belong to _________.
A.
Introduction
B.
Purpose
C.
Method
D.
Product
【判断题】The research design specifications or the methodology used to collect secondary data should be examined to identify sources of bias.
A.
正确
B.
错误
【判断题】The research used to be interested in developing accurate visual anatomical models of organism.
A.
正确
B.
错误
【单选题】—Did Jenny clean her house yesterday? —She _______ because she was not quite herself.
A.
hadn’t cleaned it
B.
had it cleaned
C.
hasn’t cleaned it
D.
has it cleaned
【单选题】In an abstract, the main procedures or the materials and equipment used to create the final result of the research belong to _________.
A.
Product
B.
Method
C.
Introduction
D.
Purpose
【单选题】Which of the following sentencescan be used to establish significanceof the research subject in the Introduction Section?
A.
The concept of voice has become central to the study of written discourse and has been researched extensively in recent decades in the field of L2 writing.
B.
Research on evaluative language in academic texts has tended, rather, to focus her on published research articles.
C.
In this study, we used computer simulation to model the aerodynamic effect of the existing safety and comfort features.
D.
However, the resulting cover is aerodynamically ineffective due to the shape of the umbrella.
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