首页
登录
职称英语
About fifty years ago, plant physiologists set out to grow roots by themselv
About fifty years ago, plant physiologists set out to grow roots by themselv
游客
2024-01-02
7
管理
问题
About fifty years ago, plant physiologists set out to grow roots by themselves in solutions in laboratory flasks. The scientists found that the nutrition of isolated roots was quite simple. They required sugar and the usual minerals and vitamins. However, they did not require organic nitrogen compounds. These roots got along fine on mineral inorganic nitrogen. Roots are capable of making their own proteins and other organic compounds. These activities by roots require energy, of course: The process of respiration uses sugar to make the high energy compound ATP, which drives the biochemical reactions. Respiration also requires oxygen. Highly active roots require a good deal of oxygen.
The study of isolated roots has provided an understanding of the relationship between shoots and roots in intact plants. The leaves of the shoots provide the roots with sugar and vitamins, and the roots provide the shoots with water and minerals. In addition, roots can provide the shoots with organic nitrogen compounds. This comes in handy for the growth of buds in the early spring when leaves are not yet functioning. Once leaves begin photosynthesizing, they produce protein, but only mature leaves can "export" protein to the rest of the plant in the form of amino acids. [br] It can be inferred from the passage that, in the early spring, the buds of plants ______
选项
A、export protein in the form of amino acids
B、do not require water
C、have begun photosynthesizing
D、obtain organic compounds from the root
答案
D
解析
见第二段第三、四句:根为芽提供有机氮,这对于芽(蓓蕾)在早春的生长很是必要,因为叶在那时还没有起作用。因此可推断出:在那时,植物的芽是从根处获得有机化合物的:所以选项D为答案。
转载请注明原文地址:https://www.tihaiku.com/zcyy/3326000.html
相关试题推荐
Astronautsreceive(extensive)trainingtoprepare(themselves)(both)physicall
Somepeopleprefertoworkforthemselvesorownabusiness.Othersprefert
Somepeoplethinkthattheycanlearnbetterbythemselvesthanwithateach
Sincetheexecutiveteamsofbothfirmshavecommittedthemselvestothedeal,t
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
随机试题
残疾人甲无力抚养儿子,故在儿子2岁时将其送人。儿子成年后回来找甲,甲生活困难,于
关于肺段的描述,错误的是A.在肺段内,肺动脉的分支和肺段支气管的分支伴行,肺段间
请阅读短文。 Lookingbackonmychildhood,I
功效活血行气,善于治疗风湿肩臂疼痛的药物是A.羌活 B.姜黄 C.延胡索
签署商品房买卖合同时需提供的证件包括()。A:认购书原件、定金收据原件 B:
一侧全肺切除术后输液速度应控制在A.10~20滴/分 B.20~30滴/分
缺乏编制定额的必要资料、数据时,制订定额一般采用的方法是()。A.统计计
某企业运用提前期法来确定各车间的生产任务,12月份装配车间(最后车间)应该生产到
泥质防水层施工质量检验项目包括压实度试验和()两项。A.严密性试验 B.
根据我国的相关规定,重大事故应由( )负责组织调查。A.国务院 B.省级人民
最新回复
(
0
)